30 November 2019

Queen versus Knight

Winning with queen versus knight is an elementary skill, but it is easy to falter with the wrong plan. This morning, I struggled briefly with a position that resulted from misplaying a bishop and pawn versus knight ending that I found in Rashid Ziyatdinov, GM-RAM: Essential Grandmaster Knowledge (2000).

White to move

1.Be5

Obvious first move--trap the knight.

1...Ke7 2.Kc5 Kd7 3.Kb5 Ke7 4.Kc6 Kf7

White to move

5.d6 Ke6 6.d7

6.Bd4 would have simplified matters. 6...Nf4 7.d7 Ke7 8.Bc5 and attempting to occupy the promotion square leads to a quick checkmate.

6...Kxe5 7.d8Q Nf4

White to move

I reached this position thinking it would be easier than it was. It became clear that I could use some work on elementary skills.

Elements of the Game of Chess

After several efforts, then engine checking, followed by further practice, I began to see some patterns. I then remembered an old textbook that had some exericises, William Lewis, Elements of the Game of Chess (1822). In "Lesson One" (August 2017), I discussed the merits of Lewis's approach to elementary checkmates with the queen. Queen vs. knight is the next chapter in his book.

Lewis's first position is instructive, and his solution is very close to what chess engines reveal today.

White to move

Lewis
Queen vs. Knight, 1822

1.Qd4+ Ke6 2.Ke4

Black to move 

2...Ng6

Lewis gives the variation 2...Nc6 3.Qd5+.
The engine shows that 2...Nf7 holds out one move longer.

3.Qb6+

Lewis's technique takes one move longer than the engine's top two choices.

3...Kf7 4.Kf5 Ne7+ 5.Kg5 Nd5 6.Qd6 Ne7 7.Qf6+ Ke8 8.Qe6 Kd8 9.Kf6 Nc8

White to move

10.Qc6 Na7

10...Ne7 11.Qd6+

11.Qb6+ 1-0

Lewis treats his readers to two more positions. In both cases, White has a knight-winning fork on the second move.

White to move

My students will be seeing these positions this coming week.

21 November 2019

Crushing Attack

In my coaching this week, I've been drawing on Encyclopedia of Chess Miniatures (2015),  by Branko Tadić and Goran Arsović. For example, one student who works with me individually chose the Queen's Gambit, and we quickly went through six games that began 1.d4 d5 2.c4 c6. This afternoon at an after-school chess club, the students chose the starting moves 1.c4 Nf6 2.Nf3 e6. It took me a few minutes to find a game with these moves, and they were played in a different sequence. The winning combination proved to be quite instructive.

Stefanova,Antoaneta (2546) -- Dzagnidze,Nana (2550) [A13]
Doha FIDE GP (Women) 6th Doha (7), 01.03.2011

1.Nf3 Nf6 2.c4 e6 3.g3 d5 4.b3 d4

White to move

Here I asked the students for suggestions. We continued looking for moves that White should consider.

5.e3 Nc6 6.Bg2 e5 7.0-0 Bg4 8.h3

A young chess player suggested this plan.

8...Bh5 9.g4 Bg6 10.exd4 e4 11.Nh4 Qxd4 12.Nc3 0-0-0

White to move

13.Nxg6

I suggested that pressure along the h-file might become a problem.

13...hxg6 14.g5 Nh5 15.Rb1

Black to move

15...Kb8

We looked at the possibility of playing 15...Nf4 here. The fork, 16.Qg4+, does not win a knight, but the pin gives White a tempo.

16.Bb2 Nf4 17.Nd5

Black to move

This position is given a diagram in the Encyclopedia. I told the students that I liked White's position, and they spent a fair amount of time trying to imagine the brilliant move that Black played. No one found it.

17...Rxd5 18.Bxd4 Rxg5 0-1

We spent ten minutes trying to stop checkmate. Nothing helped. Sacrificing the queen seems to delay, but not prevent the king's capitulation.

20 November 2019

Playing Well

This game began at the end of July and finished two weeks ago. I spent a considerable amount of time playing it and am happy with my performance.

Stripes,J. (2242) -- Internet Opponent (2189) [D11]
Chess.com, 28.07.2019

1.d4 Nf6 2.Nf3 d5 3.c4 c6 4.e3

Why choose the second most popular move? In this case, my intention was to gain experience. I seem to recall also that my opponent's game history showed that he sometimes faltered against this line in the past.

4.Nc3 has been my normal move OTB, but I have played others.

4...Bg4 5.h3 Bxf3 6.Qxf3

I had the Black side of this position in two blitz games nearly twenty years ago, but this game was was my first experience from the White side.

Black to move

6...e6 7.Bd3

PowerBook shows a 62% scoring percentage for White.

7...Nbd7 8.Nc3 Bd6 9.cxd5 exd5 10.g4

Still playing the percentages. 66.7% for White.

10...Nb6

My opponent chooses an obscure move that has produced a handful of draws. The percentages no longer have any significance: too few games.

White to move

11.g5

11.Bd2 was the alternative and I examined four games where this move had been played.

11...Nfd7

Two previous games games have reached this position.

12.e4

12.h4 led to a win for White. 12.e4 led to a draw. However, 12.e4 looked more promising to me because the imbalance in the reference game seemed to offer better prospects for seeking a win.

12.h4 Qe7 13.Bd2 Nc4 14.Bxc4 dxc4 15.Ne4 Bb4 16.a3 Bxd2+ 17.Nxd2 Qe6 and White went on to win a long game. Dvirnyy,D (2543) -- Gomez,J (2492) Baku AZE 2016.

12...dxe4

12...c5 13.dxc5 Bxc5

13.Qxe4+

13.Bxe4 might be better, according to postgame engine analysis. I probably looked at it, but opted to follow my reference game. More often than not in my correspondence experience, my opponent deviates from a single reference game before I do. Sometimes the novelty is an error.;
My notes show that I considered  13.Nxe4 Bb4+ 14.Nc3.

13...Qe7

White to move

14.Qxe7+

I chose to continue following the reference game.

14.Be3 Qxe4 15.Bxe4 0-0-0;
14.0-0 0-0-0 would have led to an interesting battle, but I thought Black was better.;
14.a4 was also a move that I considered.

14...Bxe7 15.Be3 0-0-0N

Now we are on our own.

15...Rd8 16.0-0-0 Nf8 17.h4 Ne6 18.Be2 Nc7 White's isolani may become weak and it is hard to see how the bishop pair will prove advantageous. These moves were played in a game that was drawn after 69 moves, Likavsky,T (2494) -- Antoniewski,R (2510), Austria 2008.

16.0-0-0

16.0-0 strikes me as a candidate move, as does 16.a4 with the same idea: storm the opponent's castled king while withstanding the same from him.

16...g6 17.h4 Nf8

Even though we have departed from theory, this knight maneuver has been played before. It makes sense to bring pressure upon White's queen pawn.

White to move

18.Kb1

I was not sure how to proceed, so I made a waiting move.

18...Ne6 19.Be4

Is d4-d5 a threat? I'm not certain.

19...Nd5?!

I do not think that opening the c-file is in Black's interest. However, after this move my d-pawn becomes slightly less vulnerable, I may be able to use the c-file for my rooks, and Black also gets an isolated pawn.

20.Nxd5 cxd5 21.Bf3 Kb8 22.Bg4

I want to push my f-pawn

22...Bd6 23.Rd3 Nf4?

White to move

24.Bxf4

I happily give up the bishop pair for gain of a pawn.

24...Bxf4 25.Rf3 Bc7

White to move

26.Re1!

Black's f-pawn is going nowhere. I will get a pig.

26.Rxf7 Rdf8 27.Rxf8+ Rxf8 28.f3 looked drawish to me.

26...Bb6

26...Rhe8 27.Rxe8 Rxe8 28.Rxf7 Rh8 29.Be6

27.Rxf7 Bxd4

27...Rdf8 28.Ree7 Rxf7 29.Rxf7 Bxd4 30.Be6

White to move

28.Ree7 1-0

I like my position, but I don't think my opponent should have resigned so soon. I was rather looking forward to the endgame.

05 November 2019

Positions from Recent Lessons

[T]actics flow from a positionally superior game.
Bobby Fischer, My 60 Memorable Games (1969)

My posting here has been sporadic lately. Between work and home maintenance, I've barely had enough time in the woods for hunting. As a consequence, there is no time for writing. Nonetheless, I've been teaching several individual students and running an after-school chess club. The positions below are from some classic games that were part of my instruction in October.

White to move

William Steinitz (still spelled Wilhelm at the time) did not make the computer's choice here, but it was a decisive move that forced matters. It also set up the theme for the next two positions. From Steinitz -- Mongredien, London 1862.

White to move

From Steinitz -- Mongredien, London 1863.

White to move

This was the position where Fischer made the comment in the epigraph above. From Fischer -- Sherwin, 1957.