Windmill!

Black threatens checkmate, but it is White's turn and both of Black's pieces threatening mate will soon be gone.

Rook vs. Bishop

A Technical Endgame

When I reached this position yesterday, I was about a minute behind on the clock in a game where I had difficulty getting an advantage against a much lower rated opponent. Only when he walked into a knight fork that gave him a choice of losing a bishop or the exchange did the game seem to be going my way. I had White.

White to move

31.Nxf4+! Bxf4

31...Kf6 32.Kb3 Nd1 33.Nd3 might have forced me to work harder.

32.Kxb2 Kf6 33.f3

While reviewing the game, I thought this move was an unnecessary loss of tempo. The pawn can move when g4 is attacked. Better, it seems to me was to create some threats with my rook. Even so, this is not so easy, For instance, 33.Rh8 b6 34.Rc8 c5 35.Ra8 a5 and I'm not sure how to proceed.

33...b6 34.Kb3 a5 35.Rh8 Ke7 36.Rc8 Kd7 37.Rf8 Ke7 38.Rg8 Kf6

White to move

39.Ka4

39.c5 b5 40.Rc8 seems better. I have been moving fast, too fast and still have 5 minutes remaining in a ten minute game.

39...Ke7 40.Rh8 Kd7 41.Rh5 Be3

White to move

42.Rf5

42.c5! Bxc5 43.Rxc5 bxc5 creates a nice problem position.

White to move

Analysis diagram

 44.c4 (44.Kxa5??=).

42...Ke6 43.Rh5 f6 44.Rh8 Kd7 45.Rh7+ Kd6 46.Rf7 Bg5 47.f4 Bh4

White to move

48.f5?!

48.Rh7 Bg3 49.g5 b5+ 50.cxb5 cxb5+ 51.Kxa5 and White is making some progress.

48...Bg5

48...Kc5 49.Kb3

49.Rf8 Kd7 50.Rb8 Kc7 51.Re8 Kd7 52.Re6 Kc7

White to move

53.c5

It finally feels as though I am making some progress. I have 3:30 left and my opponent has 4:42.

53...bxc5

Black spent 19 seconds on this move.

54.Kxa5 Kd7 55.Kb6 c4 56.Rxc6 Be3+ 57.Kb7 Bg5 58.Rxc4 Kd6

White to move

59.Re4

My plan is to leave the c-pawn as a threat that must be stopped while the rook and king force Black's bishop and pawn off the board and one of my kingside pawns promotes. So, first, Black's king must be cut off.

59...Kd5 60.Re6 Kc4 61.Kc7 Kd5 62.Kd7 Kc5 63.Ke7 Kd5

White to move

64.Kf7 Bh4 65.Rxf6 Ke5 66.Rc6 Kf4 67.Rc4+ Kg5 68.Kg7 Bg3

White to move

69.Re4

The immediate f6 was possible because the pin is met by another pin. 69...Be5 70.Rc5.

69...Bd6 70.c4 Bc5 71.Kf7 Bb4 72.Rd4 Bc5 73.Rd5 Ba3 74.c5 Kxg4 75.c6 Black resigned 1–0

My play was less that perfect, but good enough.

Half-Way

The five positions from Thomas Engqvist, 300 Most Important Chess Positions (2018) that I worked through today were all familiar from endgame work I did with a student six months ago or so. Two--a simple Philidor Position and a Lucena Position--I have been teaching eighteen years. Although review, one position composed by Max Karstedt and published in Deutsches Wochenschach in October 1909 confused me slightly because Stockfish made a move that differed from the solution that I knew.

In my struggle with the difference, I made an inaccurate move that was still winning, except that I could not win it.

White to move

In Karstedt's solution, Black's rook is on h1. Hence, Rc6+ sets up a skewer if the rook is captured. Nonetheless, 7.Rc6+ is still the best move and after 7...Kd5, both Rc8 and Ra6 are winning with a shorter distance to mate after Ra6. If 7...Kb5, 8.Rc8 wins.

After some contemplation, I played 7.Rb1. The computer could have opted for the idea in Karstedt's study nonetheless: 7...Rg8+ 8.Kc7 Rg7+ 9.Kb8 Rg8+ 10.Kb7 Rg7+ 11.Ka6 Rg6+ 12.Ka5 Rg3 threatens mate if White promotes, so 13.Rb5+ Kd6 14.Kb6 Rg8 15.Ra5 and the pawn will promote.

Instead, Stockfish 16 played 7...Rxb1 and I spent the next ten minutes being reminded that I have not learned queen vs. rook well enough to succeed against software.

Today was the 30th day in my quest to race through this book at five positions per day instead of the recommended five positions per week. Even this relatively easy day added another item to my "to do" list that is growing because of this pace. Yesterday, three positions game me some difficulty and this morning I spend some time looking through the first few chapters of Yuri Averbakh, Rook v. Minor Piece Endings (1978). The endings of rook and pawn vs. bishop (chapter 3 in Averbakh) serve as an excellent supplement to some ideas that Engqvist introduced yesterday.

I have now completed the first 75 positions on the opening and middlegame, and the first 75 endgames in Engqvist's book. I am on schedule.

60 Days, 300 Positions: Day Twenty-four

In defiance of Thomas Engqvist's clear advice in 300 Most Important Positions (2018), I remain on track to complete the book in 60 days. Engqvist suggests five positions per week with review of the previous week's in addition to five new positions. The idea is to "assimilate the knowledge to be gained" and be able to use it for a lifetime. He warns, "If you study too many positions and gloss over them too quickly you run an increased risk of eventually losing your discipline and then forget what you once endeavoured to learn" (7-8).

There is no question that I am glossing over many positions, while I spend many hours with others. Accordingly, I am keeping track of positions or other resources that I intend to return to after concluding the 60 day sprint. Assuming that I remain on track, I will finish my first complete read of the book in the last week of February. More than likely, I will go through it again in the near future.

Today, I am running a youth chess tournament. Such an activity cuts into my study time. I will have the book with me and endeavor to work through with some attention positions 56-60. I am working from the front of the book and also from the middle. I have been through 60 endgame positions (151-210).

Books beget books. As I am reading Engqvist's text and studying positions, I am driven to some of his sources. Three positions in the section on development were taken from a game that Victor Bologan analyzes in Victor Bologan: Selected Games 1985-2004 (2007). That book was added to my personal library earlier this month and I am reading the biographical narrative with the intent to study some of the games at another time.

In the summer of 2023, I added to my library seven of the eight volumes of Comprehensive Chess Endings, edited by Yuri Averbakh. It is no surprise that Engqvist draws some positions and analysis from these books. There is more in each of them that I could be studying. When Engqvist draws a position from one of the volumes, I find myself looking at other positions nearby. 

Other books that have been referenced are among those I have occasionally dipped into and intend to again, such as Anatoly Karpov, How to Play the English Opening and Jose Capablanca, My Chess Career. Richard Reti, Masters of the Chessboard analyzes a game that Engqvist brought to my attention. On chessgames.com, Raymond Keene claims he earned many victories against the structure Black adopted in that game thanks to having studied Reti’s analysis.

Despite Engqvist's ideas about how his book should be utilized, I am enjoying and finding productive my accelerated study. Among the benefits are that I am playing fewer games online and playing somewhat more consistently. In this position from this morning, I missed an easy tactic. But it was one of only a few inaccuracies and I did a good job of depriving my opponent of any play--a theme I saw in several master games from which positions the past few days were extracted.

White to move

26.Nxg6+ should have been easy to spot, and a couple of moves later I was courting that opportunity. Even so, after 26.Qf6+, I remained fully in control and my knight is far better than Black's bishop.

Eight moves later, my position had improved while my opponent seemed to be moving backwards.

Black to move

Black attempted to bring some pieces into battle with 34.f6. My reply was not the computer's preference, but was aimed at bringing both rooks into play. Only one was needed as Black collapsed quickly.

35.Ra4 e5? 36.gxf6+ Rxf6 37.Qxe5+ Be6 38.Rxa6 Rf5 39.Ra7+ and Black resigned.

Building Pattern Understanding

My intention with my after school club on Thursday was to reinforce some opening principles by showing the students some short games where king safety or piece mobility was horribly neglected by one player. Nonetheless, most of the miniatures that I shared from memory concerned a weakened e1-h4 diagonal--an important pattern.

The first two were exceptions, but both involved quick knockouts of the Caro-Kann Defense, which should be solid. The first game was played over-the-board in 2011 when I arrived twenty minutes late for round two. 

Stripes,J. -- Opponent
Eastern Washington Open, 1 October 2011

1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Bf5 5.Ng3 Bg6 6.Nf3 h6

6...e6 or 6...Nf6 would be normal.

7.Ne5 Bh7 8.Bc4 e6 9.Qh5 Qe7

This unfortunate blocking in of the bishop is the computer's top recommendation to my surprise.

10.O-O Nf6 11.Qe2 Nbd7 12.Bf4

I wanted to maintain a piece on e5.

12...O-O-O??

12...Nxe5 13.Bxe5 and White is slightly better.

White to move

I asked the students to find my move.

13.Nxc6 and Black resigned facing checkmate or the loss of his queen.

The second game was played online. A catastrophic blunder spoiled a difficult but playable position that I have done well against.

Stripes,J. -- Internet Opponent

Chess.com 3 April 2024

1.e4 c6 2.d4 d5 3.e5 Bf5 4.h4 h6?!

4...h5 and 4...c5 both get played against me regularly.

5.g4!? Be4 6.f3 Bh7 7.e6! fxe6

7...Qd6 might be best here. I've seen it once.

8.Bd3 Bxd3 9.Qxd3

Black to move

9...Nd7??

9...e5 or 9...Qd6 are playable.

10.Qg6#

Then, I showed the students the first game in Irving Chernev, The 1000 Best Short Games of Chess (1955).

Gibauld -- Lazard

Paris 1924

1.d4 Nf6 2.Nd2 e5 3.dxe5 Ng4 4.h3??

Black to move

4...Ne3 and White resigned.

After showing this game to some online students one morning in 2021, I played the following game that afternoon. Pulling the game from my database reminded me that I played an identical game again in 2023.

Stripes,J.--Internet Opponent
Chess.com 7 October 2021

1.d4 Nf6 2.Nd2 e5 3.dxe5 Ng4 4.Ngf3 d6

Watch what develops as it will appear in another game, too.

5.exd6 Bxd6 6.h3??

Black to move

6...Ne3 7.fxe3 Bg3#

The next game was presented to the students as one that I saw at the Mead High School Chess Club about 2006, but others have played it, too. It seems that I even played it on chess.com once in 2009.

A Visitor -- A Mead Team Member
Mead High School c.2006

1.f4 e5 2.fxe5 d6 3.exd6 Bxd6 

White to move

4.Nc3??

When I've had the diagram position against Michael Cambareri, he has played 4.Nf3 or 4.d5. I usually end up losing after a battle.

My students found the conclusion quickly.

4...Qh4+ 5.g3 Qxg3+

5...Bxg3+ 6.hxg3 Qxg3# is more common.

6.hxg3 Bxg3#

This next game is the source for the banner at the top of the page. It was played online in less than a minute during my lunch break while teaching chess in elementary school classrooms.

Internet Opponent -- Stripes,J.
Chess.com 18 January 2012

1.e4 e6 2.f4 c5 3.Nf3 Nc6 4.d4 cxd4 5.Nxd4 Nf6!? 6.e5 Ne4 7.Bd3 Qh4+ 8.g3 Nxg3 9.Nf3

Black to move

9...Qg4??

9...Qh3 was best.

10.hxg3

10.Rg1 was slightly better.

10...Qxg3+ 11.Ke2??

11.Kf1 and White is much better.

11...Qg2+

White to move

12.Ke3?

Moves into checkmate. 12.Ke1 loses the rook, but holds out longer.

12...Bc5+ 13.Ke4 f5+ 

With students, I always ask them to find the only move to get out of check. En passant is difficult for young chess players.

14.exf6 d5#

The last game appears in Emanuel Lasker, Common Sense in Chess (1917), has been played by Eric Rosen more than once, and appears in his video and Lichess Study on the Stafford Gambit. I have played the entire game nine times on chess.com.

Several Players -- Stripes,J.
chess.com November 2022 - October 2024

1.e4 e5 2.Nf3 Nf6 3.Nxe5 Nc6 4.Nxc6 dxc6 5.d3 Bc5 6.Bg5??

Black to move

6...Nxe4

I played 6...O-O the first time that I found myself in this position and won after a long battle.

7.Bxd8?

White still loses with 7.Be3, the best option. Eric Rosen's study offers the variations and I showed the main ones to my students.

7...Bxf2+ 8.Ke2 Bg4#

I hope my students will guard the diagonal leading to their king and also will exploit the vulnerability when their opponent fails to do so.

Knight and Bishop Checkmate: How and Why

Is is necessary to know a checkmate that you will never need to execute? Aside from deliberate choices due to underpromotion, I have never had to checkmate with a knight and a bishop in a game. I was on the weaker side in a blitz game on Internet Chess Club 25 years ago and got a draw because my opponent did not know how to perform the mate. I saw one young student try and fail in a youth tournament, and then in the very next round have the ending again, this time with the lone king and another draw.

In one tournament that I won, my last round opponent had failed to execute the checkmate in the previous round, else he could have won the event with a draw against me.

Many players never face it.

In Silman’s Complete Endgame Course: Beginner to Master (2007), Jeremy Silman writes:

I heretically decided not to include Bishop and Knight vs. Lone King because it’s far from easy to master, and it occurs very rarely in over-the-board play. In fact, I only got it once in my entire career, while IM John Watson and IM John Donaldson never got it at all! Is such a rarity really worth the two or three hours it would take to learn it? I say no. (xv)

On the other hand, Thomas Engqvist in 300 Most Important Chess Positions (2018) considers it of such importance that three of the 300 are concerned with this checkmate. Acknowledging its rarity (“it will probably happen once or twice in your life”), Engqvist states:

I used to teach children this endgame at a very early stage and they should know how to do it before they reach an Elo rating of 1500 to get a good feeling for how knight and bishop can harmonise together like a bishop pair. (184)

Practicing positions with few pieces develops understanding and appreciation of each piece’s unique capabilities. As Vasily Smyslov stated in Vasily Smyslov: Endgame Virtuoso (1997), "the properties and peculiarities of the pieces are most clearly revealed in the endgame" (6). Most chess study positions involve knowledge and skills that will be applied to other positions.

Yesterday, using the useful “Table of Computer Database Results for Pawnless Endings” in Karsten Müller and Frank Lamprecht, Fundamental Chess Endings (2001), I set up the knight and bishop ending that is longest distance to checkmate and played it against Stockfish. After my first five moves, I reached this position and noted the wall created on the central squares by the bishop and knight.

Black to move

I also worked through the three positions in Engqvist’s book. The first two involve the technique I have learned, forgotten, and relearned (see "Bishop and Knight Checkmate"). The third position is presented to teach the technique in lessons for beginners on Lichess that I have criticized it as more difficult.

It comes from Andre Chéron, Lehr-und Handbuch der Endspiele (1964). With Engqvist’s encouragement, I decided it was worth learning. It was not as difficult as I had thought and I spent some time practicing against the computer.

Then, I searched ChessBase Mega 2024 for endgames that reached a knight and bishop against a lone king. There are many more than I expected. Finding one that ended in a draw, I started going through the game. At several points where I thought I saw an improvement, I played from that position against Stockfish. Then, I used Stockfish and tablebases to identify areas where my play could be improved.

This exercise showed me that knowing more than one technique for executing the checkmate had practical implications. In a game, one might find one of the techniques is much faster than the other.

Here are some positions from that game. I do not know how much time pressure existed when the player was unable to finish successfully. An internet search turned up tournament information that listed the Black player’s rating as 1850.

Black to move

Black can force checkmate in 8 moves. The game went on another 20.

Nine moves earlier, Black had a mate in 9.

Black to move

A few moves prior, Black had a mate in 15, did not play it perfectly, but made progress as White did not offer the best defense.

Black to move

The closest Black came to finishing was mate in seven.

Black to move

109...Be3 (or Bf4, Bg5, Bh6) should be played, forcing White to the a-file. 110.Ka3 Kc3 111.Ka2 Bc1 and the bishop occupies the critical diagonal. 112.Kb1 Nd3 113.Ka2 Kc2 114.Ka1 Bb2+ 115.Ka2 Nb4#.

Students wanting to learn this checkmate could start with positions where checkmate can be forced in three to six moves and build from there.

Some Knight Endings

After working through the 13 knight endings in Thomas Engqvist, 300 Most Important Chess Positions (2018) over the course of several days, I put together five endings to play with some of my students. Two were from Engqvist and the others were found using ChessBase 17's research feature.

Black to move

From Sulistya,M. -- Slingerland,C., Timisoara 1988

As I beat Stockfish 16 rather easily from this position after forcing an exchange of knights, I hoped my students would do the same. That they did not suggests we might do more work on endings with a pawn majority and no pieces.

Black to move

This one is in Engqvist and from a game I cannot locate in databases: Gebhardt -- Bellman, Levelezes 1996. It is a good one to practice with. Stockfish evaluates Black's advantage as less than a pawn. I was lucky to get a draw with Stockfish 16 while playing Black. Well, not actually luck; I used the takeback feature.

White to move

In Pohjala,H.--Sulskis,S., Jyvaskyla 2013, White missed a chance for equality from this position. Against Stockfish on the iPad, I was able to hold the draw. Maybe I'll see if I can do the same against Stockfish 16 on my computer.

White to move

This position arose in Rossetto,H.--Stein,L., Amsterdam 1964 and Black won after a long struggle. The engine says the position is equal. I have not tested myself against the machine with this one.

Black to move

Black is slightly better and went on to win from this position in Lasker,E.--Nimzowitsch,A., Zurich 1934. Engqvist has this one in his book. Stockfish does not find fault with 35...h5, which all of my students played, but it seems the me that White might have more difficulties if that pawn holds back a bit.

Go to the Source

Three of the past four days, endings with a knight against pawns have been the focus as I am racing through Thomas Engqvist, 300 Most Important Chess Positions (2018). One of the positions and some of the analysis is from Yuri Averbakh and Vitaly Chekhover, Knight Endings, trans. Mary Lasher (1977). As this book was one of many that I acquired the year prior to turning 64, I pulled it from the shelf and began reading it (see "64 Endgame Books"). I skimmed the first two chapters and then looked at the analysis Engqvist referenced. 

Engqvist reaches position 41 in Knight Endings via a variation from a game played in Paris in 1848. This game is not in ChessBase Mega 2024, nor on chessgames.com, nor, as near as I can tell, anywhere else in online databases. But Engqvist offers a clue to help my search for the game: "Kieseritzky remarked that the ending was very interesting" (153).

Thanks to Chess Archaeology, it only took a minute to locate La Régence: Journal des Échecs, which Lionel Kieseritzky edited. It turns out that the source of the ending was the first game in the first issue. 

The journal offers a diagram after White's move 65. Engqvist played several training games from the position after 65...Ke5 more than twenty years before writing 300 Most Important Chess Positions. His analysis of this game, which Black could have drawn and in which both players made errors is instructive.

I played this position against the computer a couple of times on Friday and then read Engqvist's analysis more carefully yesterday. I also learned to read Kieseritzky's unusual notation: 65...E65 66. E47 E66 and entered the entire endgame into my database from the journal.

Some Easier Practice

While skimming the first chapter of Knight Endings, I paused on this statement by Averbakh and Chekhover: "Starting from any point on the board, a knight on move, can stop any pawn that has not gone beyond the fourth rank" (2).

Accordingly, I created an exercise to play against the computer. Stockfish on the iPad offered minimal resistance and was not worth the effort. I could have come to my office and used Stockfish 16 resident in Fritz, but was on the couch in the living room with my dog on my lap, so I tried using Lichess. This effort resulted in a game where I had to find a few only moves, but my composition was not as challenging as I hoped.

White to move

Almost any move works here, but I opted to only move the knight.

1.Nf7 b4 2.Nd6 Kd5

White to move

This position makes a better composition as only one move works.

3.Nf5 Ke4 4.Nd6+ Kd5 5.Nf5 Kc4 6.Ne3+ Kd3

White to move

7.Nd1

Only move, as are the next three. But they are not difficult.

7...Kc2 8.Ne3+ Kd3 9.Nd1 Kc2 10.Ne3+ Kc1 11.Nc4 b3 12.Ne5 Kc2

White to move

13.Nc4 Kc3 14.Na3

14.Nb6 and 14.Ne3 also work because 14...b2 would walk into a fork. I opted for the elementary 14.Na3 because of a known pattern.

14...b2 15.Nb1

The game went on until move 28, but there are no difficulties.

Principle of Development

The first task of a chess player at the beginning of a game is rapid development. This means that a player should deploy the maximum number of pieces on squares where they are not vulnerable and work together with other pieces. They should be deployed with attention to the opponent's efforts to accomplish the same.

There are other ways to define the principle of development (see "What is Development"). The paragraph above is an effort to present the essence of the oldest definition of the principle that I have found in print. That definition is a translation of writing by Domenico Lorenzo Ponziani (although credited to Ercole del Rio by the translator). It was published in English 17 years before Paul Morphy was born (see "Principle of Development: Early History").

Morphy is usually credited as the "first player to understand the importance of swift development in open games", as Thomas Engqvist puts it in 300 Most Important Chess Positions (2018), 13. Engqvist offers 30 key positions from 24 games to articulate the concept of development in practical ways (13-32). There should be no question that Morphy's games illustrate well the principle of rapid development. They also show, as Engqvist elucidates well, how to sacrifice material to gain a decisive advantage against a player who neglects the principle.

I have spent that past ten days working through these 30 key positions as part of an effort to read the whole of Engqvist's book in 60 days (see "60 Days, 300 Positions: Day One"). This morning I reviewed all thirty positions after spending some time (too little) on numbers 26-30. I noted the key ideas that Engqvist offers through these positions, questioning how much was absent from Ponziani's articulation of the principle.

Engqvist includes center control, which I do not see in Ponziani's statement. He also shows Morphy's preference for avoiding "unproductive one-move threats" (14). Some of the most challenging positions in the first section of the book feature positions from modern grandmaster practice where the idea is to interfere with the opponent's harmonious development. The translation of Ponziani states, 

Whoever, at the beginning, has brought out his Pieces with greater symmetry, relatively to the adverse situation, may thence promise himself a fortunate issue in the prosecution of the battle.
J.S. Bingham, The Incomparable Game of Chess (1820), 32.

In the context, I suspect that harmony might make more sense than the word symmetry, but I have not examined Ponziani's Italian. Nonetheless, it is clear that the notion of attentiveness to the opponent's development exists in Ponziani's formulation.

William Steinitz is often credited with articulating the principles underneath Morphy's play. But, clearly other chess writers before Steinitz mentioned the principle of development. As for Morphy being the first to understand rapid development, I offer this position, which would be in my collection of 300 most important positions.

White to move

White has already sacrificed two pawns and here often plays 10.Qb3, sacrificing a rook for a winning attack. Black's best chance is 10...d5 11.Bxd5 O-O, as was played in Meyer,H. -- Ubbens,MH., 1926. Gioachino Greco is credited with the position and has both 10...Bxd4 and 10...Bxa1 for Black. In fact, Greco copied this position from the manuscripts of Giulio Cesare Polerio, or perhaps a book by Alessandro Salvio (see "Greco Attack Before Greco").

Searching ChessBase Mega 2024 for the position turns up nine games with 10.Qb3 prior to the first with 10.Ba3, which might be an improvement (see "Corte -- Bolbochan 1946").

After 10...Bxa1 in Polerio's composition, we have a position that I like to show students in conjunction with this position from Morphy's Opera Game.

White to move

In both cases, White is behind a considerable amount of material but completely winning because Black's pieces lack mobility. It seems clear to me that Polerio and to an even greater extent Greco understood the pitfalls in neglecting the principle of development. It remained for the leading players of the so-called Italian school a century later to articulate the principle.

Nonetheless, Morphy's games remain the clearest early examples.

Interesting Exercise

This pawn structure arises after the Spanish Exchange and a similar one, but with Black’s doubled pawns on the f-file, can arise from the Caro-Kann. Opening theory states that Black cannot allow liquidation of all the pieces because the pawn ending would be lost. Max Euwe offers analysis of how to play the pawn ending in an obscure book. Thomas Engqvist presents the analysis in 300 Most Important Chess Positions (2018).

White to move

Naturally, after reading through Engqvist’s analysis, I played the game against Stockfish. My best result after several efforts has been a draw. I lost, used the takeback feature, and tried again. In repeated efforts, I’ve blundered and lost more than I have tracked, but completed two games with draws.

The win is elusive and worth pursuing for what I can learn about pawn endings.

Today is the ninth day of my 60 day quest to go through all of Engqvist’s book at the rate of five positions per day. Yesterday, I spent a fair amount of time looking at games from which positions 21-25 were or could have been derived. For instance, one position featured a novelty played by Hikaru Nakamura in 2011. Several other players have followed his lead and I played through some of those games.

Today’s position is the 16th in the section on pawn endings. I have been alternating between openings and endings. I will finish the development section tomorrow.

Edit: after multiple efforts, I dove back into the analysis in 300 Most Important Chess Positions. I have been struggling against the engine from the wrong position. Black's a-pawn should be on a6. How much difference does this make?

Today's Position

White to move

This position is not among the five that I considered today from Thomas Engqvist, 300 Most Important Chess Positions (2018), which I am working through at the rate of five positions per day. The position does come from a game from which Engqvist extracted three positions, but it was this moment in several games that captured most of my time this morning.

This position seems to have arisen for the first time in Gelfand,B. -- Karpov,A., Sanghi Nagar 1995 and at least twice more that year.

Gelfand played 9.Nd2 and lost after a long struggle. In Anatoly Karpov, How to Play the English Opening (2007), it references 9.Ne1, first played in Gulko,B. -- Sadler,M., Lucerne 1997 as an improvement for White (47). Nonetheless, ChessBase Mega has two White wins, two draws, and four Black wins after 9.Ne1. One of the draws is Engqvist's source game.

After 9.Nd2, White has three wins, a draw, and two losses. Why is 9.Ne1 an improvement?