14 May 2014

Beware the Aggressive King

Black to move

This position arose in Bok -- Neumann, Bundesliga 2011. Analysis in Chess Informant 113/116 stops ten moves prior to this position.

Black played 38...Rh3 and was quickly lost. Did Black have a chance to draw?

13 May 2014

Transition to Philidor

The position below arose in Bologan -- Erdos, Sibenik 2011. The opening and early middle game appears in Chess Informant 113/113 stopping at a point where White, a pawn ahead, has only one move to avoid checkmate. Informant gives the evaluation that Black has compensation for the material.

Black to move

My analysis engine favors 40...exd5, which my eye likes because the White king appears cut off from the passed d-pawn. Even so, White's pawn majority should lure the Black rook to the a- or b-file.

Stockfish DD offers: 40...exd5 41.Kg3 Kxf6 42.b4 d4 43.a4 h5 44.Rb1 Ke5 45.b5

Black to move
Analysis Diagram
45...axb5 leads to a drawn queen ending. The engine favors 45...d3. That, too, leads to a draw although it is less elementary.

In the game, Viktor Erdos opted for 40...Rxd5.

The game continued 41.Re4 Kxf6 42.Ra4 a5 43.b4 axb4 44.Rxb4 Rd2+ 45.Kg3 Rxa2

White to move

White has only one move that holds the draw.

46.Rf4+

Can the Black king find shelter from the checks? Erdos sought refuge on e8, but h8 was also possible. Best play appears to lead to a draw in either case.

46...Kg6 47.Rg4+ Kf7 48.Rf4+ Ke8

White to move

49.Rf6! Ra3+ 50.Kg2 Ke7 51.Rh6 Kd6 52.Rxh7 Kd5 53.Kf2 e5

White to move

White has achieved a Philidor Position with the Black pieces one rank further back.

54.Rh4 e4 55.Rh8 1/2-1/2

08 May 2014

Lesson of the Week

Defending a Pawn

Black to move

Find Black's best move so as to not fail as Black did in this online blitz game.

The following pawn ending was reached after following the suggestions of a young player from the diagram above. It took me less than a second to declare that White is winning no matter who is on move.


Naturally, the young player did not agree with me. I played the position out against Hiarcs on the iPad to demonstrate the elementary win.

06 May 2014

Blowing an Endgame

Yesterday morning, I shared on Facebook a link to an excellent article from The Chess World, "7 Chess Training Habits You Should Drop Now." The author, Yuri Markushin, highlights several practices that develop sloppy and lazy thinking. He begins with blitz and bullet.

Last night, I played a blitz game that illustrates this problem with blitz. In contrast to calculating the consequences of a rook exchange and then playing the pawn ending correctly, I intuitively guessed that I would benefit from an exchange of rooks and then threw away the pawn ending.

Black to move

32...Re3+ was the correct move. But then, 33.Kd4 Rxa3 34.bxa3, it was time to assess the resulting pawn position.

I played 34...f5, playing hope chess. I hoped that my opponent would facilitate my dreams of a passed pawn with 35.gxf5. He refused to cooperate, playing instead 35.a4.

Did I then seriously consider 35...e5+, a move that may at least hold the draw?

No. I played 35...fxg4 and quickly reached a position that was hopelessly lost. Several moves later, we reached the position below.

White to move

My opponent wins easily with 44.Kf5. However, 44.Kd4 was played. In the ensuing pawn race, we both promoted pawns. The queen ending was a dead draw. But, as often happens in blitz, a series of senseless checks were employed to run the other player out of time.

04 May 2014

Gaining a Tempo

White intends to win back a sacrificed pawn and swap queens. But there is more. Choosing the correct move order gains a tempo by imposing upon Black an additional move. This tempo helps White maintain the initiative.

The game was Popovic -- Bogut, Hrvatska 2011 and was published as Chess Informant 113/103.

White to move

10.Bxf7+ Ke7 11.Qxd8+ Kd8 12.f4 Ke7 13.Bb3

White went on to win the game.

03 May 2014

More Rook Ending Tragicomedies

Thanks to the need to effectively teach the Lucena and Philidor rook endgame positions to a strong young chess player, I have been using my database to review my own games. My OTB (over the board games) reveal some degree of skill, but errors in blitz expose weaknesses in my intuitive understanding.

Blitz can reinforce bad habits, but it may also be useful for diagnosing and correcting those habits.

Black to move

I threw away a decisive advantage with 57...gxh3. This game was played in April 2014.

Black to move

53...Kf4 preserves winning chances, but I played 53...g4?? to reach a dead drawn ending.


The Good News

Despite these many failings, my database reveals an abundance of games in which I was able to convert a Lucena or or similar position.

This one from the Free Internet Chess Server (FICS) in February 2014 shows that I missed the best line, but found a wholly adequate solution nonetheless.

White to move

67.Rf6+ (67.Rb8 was best) 67...Kg3 68.b7 Rb6 69.Kc4 Rb1 70.Kc5 Kg4 71.Kc6 Kg5 72.Kc7 Rc1+ 73.Kb8 Rb1 74.Rc7 Kf6 75.Kc8 Re1 76.b8Q Re8+ 77.Kb7 Rxb8 78.Kxb8 and my opponent opted not to test how quickly I could deliver checkmate with a rook and king against his lone monarch.

I also avoided a trap in this finish from March 2013 on Chess.com. Then I saw a trap that was not there.

White to move

47.Kc6 Rf2 48.Kc5 Rc2+ 49.Kb4 Kc7 50.Ka3 Rc3 51.Kxb2 Rxb3+ 52.Kxb3. Game drawn.


02 May 2014

Philidor Position: Practice

Demonstrating fundamental understanding of the Philidor position in rook endings is one of the tests for the Rook Award in my series of scholastic chess awards. Naturally, when I have a student working through that stage, I spend additional time looking through my own games both to find evidence of correct play and to extract study positions where failure occurred.

Tragicomedies abound in my database of online games, which includes thousands of turn-based (correspondence) games, nearly as many "standard" (fifteen minute and longer) live online games, and fifty thousand blitz games. There are dozens of games where the last several moves clearly indicate both players trying to run the other out of time in a dead drawn ending, or even in endings where one player has a decisive advantage but the other manages to win. There are also far too many games where moves played demonstrate intuitive failure or lack of understanding of correct technique.

Using the classification keys in ChessBase 11, I am able to quickly locate hundreds of rook endings and skim through the positions rapidly. With an eye for thematic positions, I seek those with results at odds with the truth of the position. I play out the position from before the error to practice correct technique. This practice also tests my understanding of which positions are drawn and which won or lost.

As White, I threw away a draw from this position, but then won on time a few moves later. The game was played on the Internet Chess Club in August 2000.

White to move

54.Ra6?? loses to 54...Rf6+. My opponent returned the position to drawn status with 54...f4, allowing my rook to maneuver to f1 where it awaited help from its king.

My ICC opponent in 2000 could have held the next position easily by shuffling the rook across to a3, b3, ... Even 78.Rh5, the move played, could have held if not for the blunder several moves later.

White to move

78.Rh5 Kg4 79.Rh3 Re7 80.Rg3+ Kf4 81.Rg2 Rh7+ 82.Kg1 Ke3 83.Rf2?? and I won with a rook swap that took us into an elementary pawn ending. Playing my opponent's position against Stockfish DD earlier this week, I reached a draw in a few seconds of play keeping the rook on the third rank until Black advancd the pawn to f4, then keeping up a barrage of side checks.

My own errors were glaring in the next game.

Black to move

In a three minute game on ICC in 2001, I played 55...Re5?? in this position. My opponent exploited the error to win.

In this game from 2001, I maintained the draw for several moves. Even so, my moves call into question my intuitive sense. Keeping my king in front of Black's pawn should not require conscious thought.

White to move

70.Ke3 (I played 70.Kf3 against Stockfish) 70...Ra3+ 71.Kd4 Ra4+ 72.Kc3?? and I lost the game.

Improvement?

Moving forward in the database to 2006, I should find better play. By then, I had spent at least a little time learning some principles of rook endings, although serious work began in 2007. It was then that I bought Jeremy Silman's new book, Silman's Complete Endgame Course (2007) and quickly went through everything up through the chapter for C Class. In the fall of 2006, I also broke through to B Class with my USCF rating.

After studying the section on the Lucena and Philidor positions in Silman's text, I changed the requirements for my Rook Award. The Lucena and Philidor positions replaced checkmate with a bishop and a knight. Silman's arguments concerning the relative value of each influenced my decision, as did one of my pupils requiring 51 moves to checkmate my king with a bishop and knight after many attempts over several weeks.

In this game on Free Internet Chess Server (FICS), I started well.

White to move

52.Rh3+ Ke4 53.Rb3 f4 54.Kf1 f3

I have occupied the third rank. Black has advanced his pawn.

55.Rb4+ Ke3 56.Rb3+ Kf4 57.Rb4+??

I threw it away. It was time to check from the rear.

In another game on FICS in 2006, I threw away a win.

Black to move

56...f2?? leaves my king unprotected from White's checks. Against Stockfish this week, I won quickly after 56...Re1+.

Several years later, rear checks allowed my to transition into a drawn pawn ending in this game from Chess.com that was played in 2013.

Black to move

70...Rxg3+ 71.Kf4 Rg1 72.Ke5 Re1+ 73.Kd6 Rxe6+ 74.fxe6 Ke8

My opponent tested my time management skills for seven moves before we reached stalemate.

Nonetheless, failures continued to manifest themselves in 2013.

I blew a draw in this game on Chess.com.

White to move

70.Rf3+?? leads to passive first rank defense that is lost (and straight out of the textbooks).

Against the engine, I held the draw after 70.Rb6+ Kc3 71.Kb1.

As recently as January of this year, I demonstrated a continuing need for improvement.

White to move
52.Kh1

Choosing the short side is as effective here as 52.Kf1.

52...f3 53.Rc4+ Kh3 54.Rc1??

54.Rc8 would have been simple and effective. Passive defense leads to checkmate.

The work continues.

01 May 2014

Philidor Position: Historical Note

The Philidor Position in rook endings is one where the weaker side's king stands in front of stronger side's pawn, on or near the promotion square, and in which the weaker side is able to prevent the stronger's king from advancing to the sixth (or third) rank. Dvoretsky's Endgame Manual (2003) offers a typical example (145).* The position is so-named because François-André Danican Philidor was the first to demonstrate the defense in his Analysis of the Game of Chess (1777), 275-282.


With Black on move, moving the rook to almost any square along the b-file holds the draw. 1...Rb6 is the clearest and easiest demonstration of the technique. Philidor noted, "By keeping that line with his rook, he hinders your king from advancing" (275).

Mark Dvoretsky notes that Philidor thought that White could win if he were on move, but later analysis has revealed that he is wrong on this point. In Philidor's position, White is on move, but his initial setting differs in one important respect from Dvoretsky's diagram. The pawn has advanced to the fifth rank in Dvoretsky.

Philidor presents the following position.

White to move

After the moves 1.e5 Rb6 2.Ra7, the position is almost identical to Dvoretsky's with only the Black rook on a different square. With Black on the move, Dvoretsky's key move creates the position in Philidor's analysis, but in Philidor Black is still on move. In some positions, such a transfer of the side to move proves critical, but here it is not so.

Philidor gives 2...Rc6 with the comment: "He ought not to depart from this line with his rook, but at the very instant when you push your pawn" (277).

3.e6 Rc1

"If he had given check, he would have lost the game" (Philidor).

4.Kf6 Rf1+

Philidor asserts, "He must continue to give you check, in order to drive you away from your pawn; and at the very moment when your king falls upon his rook, he will attack and take your pawn" (277).

Philidor's Back-Game**

Philidor's analysis of the position where he asserts that White may win begins from his diagram and offers Black moving first, 1...Ra1.

White to move

We see the essential elements here are the same as in Dvoretsky's position with White to move.

2.Kf6 Rf1+ 3.Ke6 Kf8 4.Rh8+ Kg7 5.Re8

Philidor states that this move is the only one that "can insure the game" (279). Checking the position with tablebases confirms that Philidor was in error, as noted by Dvoretsky.

5...Re1 6.Kd7

Black to move

6...Kf7

This move is the key error. Philidor offers an alternative in the notes: 6...Rd1+ 7.Ke7, but he misses the key defensive idea that was discovered by later analysis, 7...Ra1!

7.e6+ Kg7 8.Ke7

Here, White missed the winning 8.Ra8 (also Rb8, Rd8, and Rc8).

8...Re2+-

8...Ra1 draws, again.

The rest of Philidor's analysis is a good illustration of a winning technique that works in some Lucena positions, but differing from the orthodox bridge building on the fourth rank.



*Other books offer slightly different positions. Silman's Complete Endgame Course (2007) has 6R1/4k2r/8/3KP3/8/8/8/8 (126). Fundamental Chess Endings (2001) by Karsten Muller and Frank Lamprecht has 1r3k2/R7/8/5PK1/8/8/8/8 (177). Grigory Levenfish and Vasily Smyslov, Rook Endings, trans. by Philip J. Booth (1971) has a partial mirror image of the position in Philidor's text: the White king is flipped to the other side of the pawn and the rooks have swapped rook files. It is 4k3/R7/7r/3K4/4P3/8/8/8 (15). Reuben Fine, Basic Chess Endings (1941) is almost identical to Philidor's with only the Black rook one square to the right (287).

**Back-game was the term employed for variations in seventeenth and eighteenth century chess texts.