30 November 2011

Latent Tactics

Lesson of the Week

A jury of Grandmasters votes on the best games of each issue of Chess Informant. For Informant 105 (2009), Topalov -- Kamsky, a rapid game played in Nice, France, placed second. This win with Black by Kamsky demonstrates how a queen and knights can exploit disharmony among the enemy forces. My lesson for young chess players this week, however, is more elementary: simple tactics latent in a complex position.

Topalov still had chances to gain an advantage from the position after Black's fourteenth move.

White to move

The game was annotated for Informant by Sergei Shipov. He marked Topalov's move, 15.b4, as dubious. According to Shipov, White would have had a slight advantage after 15.Be3. I ran some engines on the position and learned that Be3 is Rybka's second choice and Houdini's first. Rybka's top choice is also the choice of Stockfish: 15.Qa2.

The second choice of Stockfish was the first move that I considered, and it, too, is covered in Shipov's annotations. In the variation that he gives are some instructive tactics suitable for elementary players.

15.Nxb7 (variation given by Shipov, Informant 105/48)

It often seems sensible to exchange a knight for a bishop, and in this case it clears the way for the win of a pawn, or so it seems after shallow analysis. But, deeper into the line, we see that White does not retain the extra pawn and comes under an attack that demonstrates the advantage has shifted to Black.

15...Qxb7 16.Qxa6?! Shipov marks this move as dubious, although it is the logical idea behind 15.Nxb7.

16...Qxa6 17.Rxa6 Nc5

The Black knight forks pawn, bishop, and rook. As either the bishop or rook must succumb, the logical move is to attack Black's undefended bishop.

White to move

18.Ra7 Bd8!

In Shipov's line, Black keeps the bishops on the board. Frequently, maintaining a bishop pair is an advantage in top-level chess, but Black's knights are the powerful pieces in this position, just as they were in the actual game. In this variation, Black's dark-squared bishop also has come to life.

19.Bc2 Bb6

Shipov's variation ends here with the assessment that Black has a slight advantage and an attack, although still one pawn down.

White to move

Even beginning players should be able to see that 19...Bb6 attacks the rook, and that after it moves to safety, the bishop checks the White monarch as soon as the Knight on c5 moves. Play might continue 20.Ra1 Nxe4+ 21.Kh1 Nxc3 22.bxc3. Black has regained the pawn and shackled White with doubled pawns on the c-file. Part of the idea behind 15.Nxb7 was to create a passed b-pawn, but that idea failed.

20 November 2011

Press the Attack

This afternoon, in a make-up game for the Turkey Quads, I had White in this position.

White to move

How should White press the attack?

19 November 2011

Choose your Endgame

When a player is ahead by a pawn, which is more favorable: rook versus rook or same color bishops?

In the Turkey Quads on Thursday night, my opponent faced this choice.

White to move

I expected 52.Ra8 Ra2+ 53.Kg3 Bc4 54.Rxa2 Bxa2, and then I must defend a position where his bishop is the wrong color for the h-pawn, but the e-pawn represents a significant threat.

White to move

My opponent opted to exchange bishops. 52.Bxa6 Rxa6, and I was left defending with the rook. Having spent a fair amount of time last spring studying some of Vasily Smyslov's rook endgames, I played with some confidence that I could find the correct moves and hold the position.

See "Rook Endgame: Critical Position," "Play like Smyslov," and "The Active Rook."

White to move

Did my opponent make the wrong choice on move 52? Did he have better chances in a bishop endgame? I think so, but am not certain. Chess engines are not particularly helpful evaluating such positions as they may give +2.50 in positions that are theoretical draws.

15 November 2011

Lesson of the Week

The Games of Gioachino Greco

Gioachino Greco recorded a number of games in his chess notebooks beginning as early as 1619. As he traveled from his native Italy to France and England, he sold copies of these games to patrons who sought chess instruction from him. These games are some of the oldest recorded complete games of chess available. They offer many useful lessons in chess tactics.

This week, we are highlighting a few key positions from two of these games.

Black to move

Black to move

Black to move

In addition to tactics, principally discovery, students should learn to examine king safety and material imbalance while studying these positions.

The Games

Here are the game scores from which these positions arose. Both games are identical until White's tenth move.

NN - Greco,Gioacchino [C50]
Europe 1620

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.0–0 Nf6 5.Re1 0–0 6.c3 Re8 7.d4 exd4 8.e5 Ng4 9.Bg5 Nxf2 10.Qb3 dxc3 11.Bxd8 cxb2 12.Nc3 Nd1+ 13.Kf1 bxa1Q 14.Rxd1 Qxd1+ 15.Nxd1 Nxd8 0–1

NN - Greco,Gioacchino [C50]
Europe 1620

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.0–0 Nf6 5.Re1 0–0 6.c3 Re8 7.d4 exd4 8.e5 Ng4 9.Bg5 Nxf2 10.Bxd8 Nxd1 11.Rxd1 dxc3+ 12.Kf1 cxb2 13.Nbd2 bxa1Q 14.Rxa1 Nxd8 0–1

11 November 2011

Castling Queenside in the Queen's Gambit

I won my game in the Turkey Quads last night, but I was not happy with my opening. It seemed to me that Black too easily gained equality, and perhaps even had chances for the advantage. My opponent missed these chances, but lingering doubts concerning my play through the first ten moves or so haunt me. Hence, I was digging into the Encyclopedia of Chess Openings when I found a curiosity: 10.O-O-O.

A search of Chess Informants 1-103 (I need to buy the past two year's issues to bring my collection up to date) turns up two games, both embedded into ECO: Ree - Pfleger 1966 Informant 1/366, and Ftacnik - Zaw 2000 Informant 80/465. Searching the larger databases in ChessBase 11 produces more games, earlier games, and the information that GM Ľubomír Ftáčnik is the "strongest player" who has employed this line. Perhaps Akiba Rubinstein was stronger, but he played prior to FIDE adopting an Elo rating system, and so CB 11 ignores his efforts in the data field reporting "strongest". Alexander Alekhine played it once in a simul, as well, but he lost. Boris Spassky reached a similar position after 8.O-O-O, and the line appears in ECO (Informant 2/507).

ChessBase Online contains forty-seven games with the position from ECO in the image above. White scores a shocking 70.2% in these games. Of course, some of these games in the database are between relatively weak players. Most are interesting games between masters.

White's plan is not difficult to fathom: an all-out assault on the enemy king. Black must seek counterplay that exploits the half-open c-file. White's attack is already better prepared, so Black's task is difficult. There were eleven games 1905-1966 with ten White wins and Alekhine's loss. The first draw occurred in 1971.

Black's most popular replies are 10...Ne4 and 10...c5, but Win Lay Zaw's 10...Re8 deserves scrutiny. Zaw was not the first to play this move, which appears one other time in the ChessBase database. Zaw's novelty came on the next move, 11...Nf8. In the Informant annotations, Ftacnik points out a draw that Zaw missed near the end. Zaw's pawns nearly rolled over the top of White's position down the center.

I am looking through these games, which offer some interesting study material featuring attack and counter-attack.

09 November 2011

Learning from Greco

Gioacchino Greco was a chess teacher four centuries ago. The small selection of his games, likely created as lessons rather than a record of actual games, serve as a useful primer in chess tactics. The ChessBase online database contains eighty-three such games, including quite possibly the first smother mate.

These games can be accessed via the ChessBase iPad app, and of course through any of several ChessBase programs. While ChessBase 11 offers the quickest access, and the easiest structure for saving, analyzing, and recording comments, the iPad app offers quick access from anywhere the user has a connection.

NN - Greco,Gioacchino [C30]
Europe, 1620

1.e4 e5 2.f4 f5 3.exf5 Qh4+ 4.g3 Qe7 5.Qh5+ Kd8 6.fxe5 Qxe5+ 7.Be2 Nf6 8.Qf3 d5

This position appears to me to be the first of several critical positions. I do not like 9.g4, Greco's move, and would favor moving the d-pawn forward. No analysis engine is available within the Chessbase app, forcing me to rely upon my own resources. I like 9.d3 to bring the dark-squared bishop into play, and perhaps find security for the king by castling that direction.

By calling up Greco's games in ChessBase 11, I was able in less than five minutes to create a PGN database of his games in my Dropbox folder, and then open this database in tChessPro, another iPad app. That app has a built in chess engine.

The tChess Pro engine likes Greco's move better than I do, but agrees with my assessment that after 9.g4 h5, White should thrust the g-pawn another square forward. For the record, Rybka 4 prefers 9.d4.

9.g4 h5 10.h3 hxg4 11.hxg4 Rxh1 12.Qxh1 Qg3+ 13.Kd1 Nxg4 14.Qxd5+ Bd7 15.Nf3

White's play offers a series of instructive inaccuracies. After this final error, checkmate is forced.

15...Nf2+ 16.Ke1 Nd3+ 17.Kd1 Qe1+ 18.Nxe1 Nf2# 0–1

08 November 2011

Lesson of the Week

Checkmate skills

For the beginning players, this week's lesson is an effort to reduce the unnecessary draws in scholastic tournaments. At Saturday's tournament, it seems that every round had at least one player chasing the opponent's king around the board with a queen: check, check, check, ... but never checkmate. Checks can be useful in the drive towards checkmate, but children have an easier time learning the correct technique if they are not allowed to check. For this training exercise, we introduce an artificial rule: no check that is not checkmate.

Players on the attacking end need to learn to control without checks

Players on the defending side of these efforts, if they are not writing their moves, should ask for a judge to begin counting moves so that a draw by the fifty-move rule becomes a valid draw claim. Normally, a record of the moves is the necessary prerequisite for making a draw claim by the fifty-move rule, or draw by repetition. For beginning students who are playing in tournaments before learning to record the moves, a compromise is helpful. For this reason, we permit a judge to count moves upon request of a player.

Queen vs. King

Start with a king and queen of opposite colors. The player with the queen is not permitted to deliver check.  The queen must drive the king to the edge of the board and towards the corner.

White to move

When the defending king is reduced to two squares, the other king appears in the far corner. Now, it is checkmate in six moves. The attacking player still delivers no checks until the checkmate. The key to quick reduction of the defending king's space is to move the queen a knight's move from the king.

White to move

Keep practicing this elementary skill until the moves feel automatic. It is important to learn to control the king by restriction, rather than assault. Reduce his choices.

Rook and King vs. King

Players who have mastered the elementary checkmate of queen and king against king are ready for one that is more challenging. A rook cannot drive a king to the edge without assistance. But, a rook and king working together can drive the king to the edge without checks.

White to move

In our starting position, White can force checkmate in sixteen moves. With our artificial rule in place, it will take more. The rules of chess allot fifty moves. A skilled player should be able to deliver checkmate in less than thirty without having checked the king prior to checkmate.

The rows of red squares mark a barrier that the king cannot cross. At the start, the Black king is trapped in a grid of thirty-six squares. White makes this grid smaller and smaller until checkmate becomes possible. The King might be checkmated anywhere along one of the edges.

To illustrate correct technique, I played against Rybka 4, an extremely strong chess engine.  First, I moved my rook far from the other king along the b-file. Then, I brought my king forward. My king kept marching until my rook was in danger.

Stripes,James - Rybka 4 x64
Blitz 5m Spokane, 08.11.2011

1.Rb7 Kd3 2.Kb2 Kd4 3.Kc2 Kd5 4.Kd3 Kc6 

White to move
Black threatens White's rook


The rook moves to safety. Black's grid, or corral, has been reduced to twenty-four squares.

Black to move


If Black tries 5...Kc5, attacking the rook again, then 6.Rd4 reduces the grid to twelve squares.

6.Kd4 Ke6 7.Rb5 

Black to move
White was concerned about the square f5

7...Kf6 8.Re5
Black's corral had become smaller: nine squares.

Black to move

8...Kf7 9.Kd5 Kf6 10.Kd6 Kf7

White to move
Time to move the rook

Black to move
Black has six squares

11...Kf8 12.Re7 

Black has three squares.

12...Kg8 13.Ke6 Kf8

White to move
Which piece should move?


14.Rf7? is a typical beginner's error. From a corral of three squares, the defending king has been given a choice of two corrals: two squares or five squares. Nearly every check offers similar choices. To win efficiently, White must reduce Black's choices.

14...Kg8 15.Kg6 Kf8

White to move
Any yellow square
We have reached a position that a clever student might recognize as bearing similarity to Problem 9 in Bruce Pandolfini, Pandolfini's Endgame Course (1988). White must keep the Black king from e7 and e8 (red squares), forcing the king to g8 (green highlight). Moving the rook to any yellow square accomplishes this objective.

16.Re5 Kg8 17.Re8# 1–0

07 November 2011

Tactics Training: Shredder iPad App

Back in January, my initial review of iPad chess applications highlighted Shredder as an exceptional playing program. I noted then that it also comes with one thousand tactics exercises. Although these exercises are not technically difficult, they must be solved quickly to get full credit. Many of the problems are on par with the vast majority found in Fred Reinfeld, 1001 Winning Chess Sacrifices and Combinations (1955). Some are much simpler, requiring the solver to notice a piece that is en prise.

Problem Number 703
Mike Klein, "Comparing Apps to Apps," Chess Life (October 2011) also recommends Shredder, although his comments might carry more weight if he had tested tChess Pro, which has far better database features than found in the two apps that he recommended for that purpose.

In Shredder, each training problem must be solved before moving on to the next. As time is expended, the number of possible points earned diminishes. Wrong answers diminish the score more rapidly. After too much time, or a couple of wrong answers, the score will be zero. Even then, the problem remains before the solver until a solution is found. In the upper left-hand corner is a question mark. Touching this image causes the piece to be moved to flash. Trial and error, if it comes to that, will eventually reveal the correct move.

Playing and Puzzle Ratings
Some problems require six moves or more. Many are one or two moves deep. Shredder tracks progress: total score and percentage of possible points. These data is provided for both the whole set, and for the past ten problems. This data can be reset to the beginning.

The Shredder app is not my only resource for tactics training, and so I do not use it every day. I have completed just over seven hundred of the thousand.

Capturing the screenshot and solving the problem above took me less than half a minute. That was long enough to lose one point. After playing Bxc5, a message appears: "You have solved this puzzle and get 9 points!" The message offers two options: stop, which ends the session, and next puzzle, which brings up the next exercise. If it is Black to move, the board will flip. The opponent's previous move is always shown, which eliminates ambiguity concerning whether an en passant capture would be possible. I vaguely recall that such a capture was the correct first move in at least one of the problems.

I plan to complete all one thousand problems, and then begin anew, going through the set a second time with more discipline and consistency. My principal objective the second time through will be to improve my scoring percentage.

06 November 2011

Teaching the Rules of Chess

A Beginner's Confusion

At a youth tournament yesterday, I was called in by a judge to deal with a case where one player insisted that he had checkmated his opponent. The checkmated player did not understand that he was in checkmate. I had taught him to play when I taught the game in his first or second grade classroom. As a second grader, he was part of an in-school chess club that I run. Now in third grade, he is part of an after-school club. I continue to teach the basic rules in these clubs. Some of these children do not play chess at home.

The diagram below shows the essentials of the position. There were perhaps another dozen pieces on the board, more white than black.

Black to move

I asked him to show me where his king could legally move. The youth's argument was thus: if I move to f7 and he leaves his queen there, I can capture the queen on the next move. Can the queen capture your king, I asked. "No, you're not allowed to capture the king," he replied. But, I told him, you're not allowed to move your king where it may be captured. Is there any square where your king can move that it cannot be captured? We went a few rounds with this conversation before he acknowledged that he was indeed in checkmate.

Teaching the Rules

How does one explain the king's movement, check, and checkmate to young children? Do many chess teachers say that a player cannot capture the king? I've heard chess coaches tell children, "you cannot capture the king, you must checkmate him." I have expressed the basic rules in terms of a paradox: the object is to capture the king, but the king cannot be captured.

FIDE Rule 1.2 supports this notion:
Leaving one’s own king under attack, exposing one’s own king to attack and also "capturing" the opponent’s king are not allowed. The opponent whose king has been checkmated has lost the game.
FIDE Handbook, http://www.fide.com/fide/handbook
How does this prohibition against capturing the opponent's king function? If it is possible to capture the king, what must be done? If the king is in checkmate, the game is over. But, what do we do if the players failed to notice the check? What may be done if the player moved into check?

FIDE Rules, Article 7 addresses irregularities, including illegal moves.
If during a game it is found that an illegal move, including failing to meet the requirements of the promotion of a pawn or capturing the opponent’s king, has been completed, the position immediately before the irregularity shall be reinstated. (7.4.a)

After the action taken under Article 7.4.a, for the first two illegal moves by a player the arbiter shall give two minutes extra time to his opponent in each instance; for a third illegal move by the same player, the arbiter shall declare the game lost by this player. (7.4.b)
The position prior to the illegal move must be restored, and the game recommence by a legal move. In classrooms, I teach the children to politely request that their opponent recognize the check, take back the illegal move, and make a move that does not leave the king in check.

Sometimes the children learn these rules incompletely.

02 November 2011

Lesson of the Week

Deflection and Decoy

A short game offers illustration of some basic tactics.

Stripes -- Yaelg
SocialChess Internet, 2011

1.d4 c5 2.d5 e6 3.c4 Qa5+ 4.Bd2 Qa6 5.e4 exd5 6.cxd5 c4 7.Qc2 Bb4 8.Bxc4 Bxd2+ 9.Nxd2 b5

White to move

White's move was an effort to deflect the Black queen from defense of Black's vulnerable back-rank. Deflection is a special case of removing the guard that draws an enemy piece away from a key square.

10.Bxb5 Qxb5 

10...Qb7 is better. The deflection is not forced.

11.Qxc8+ Ke7 12.Ngf3 Qxb2 
White to move

13.d6+ Kxd6 

White's pawn sacrifice decoys the king onto a square where it is vulnerable to a fork that wins the queen. Decoy draws an enemy piece onto a vulnerable square.

13...Ke6 only delays the coming fork. 14.Qe8+ Kf6 15.Qd8+ Ke6 16.Ng5+ Ke5 17.Nc4+

14.Nc4+ Ke7 15.Nxb2 g6 16.0–0 f5 17.exf5 gxf5 18.Rfe1+ Kf7 19.Qe8+ Kg7 20.Rad1 h5 21.Rd6 Rh6 

White to move

White has a choice of two ways to force checkmate in five moves.


The other possibility is 22.Rxh6 Kxh6 23.Ne5 Ne7 24.Qh8+ Kg5 25.h4+ Kxh4 26.Qf6#

22...Nxe7 23.Qxe7+ Kg8 24.Rxh6 Nc6 25.Rg6+ Kh8 26.Qg7# 1–0

01 November 2011

Something is Wrong

Game list view in CB Online for iPad
While I continue exploring the features of several iPad chess apps, I was looking through the games of Robin Edlund with the CB Online app. I know next to nothing of Edlund, except that his annotations to his loss in Chess Informant 90/245 provided the suggestion that led to a win for me.

His earliest loss in the database seems amiss. The game ends with his opponent in check and soon to lose his queen.

Edlund,Robin -- Tikkanen,Anders [B17]
Hallstahammar op Hallstahammar (5), 1995

1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nd7 5.Nf3 Ndf6 6.Ng3 Bg4 7.Be2 e6 8.0–0 Bd6 9.h3 Bxf3 10.Bxf3 Qc7 11.Ne4 Nxe4 12.Bxe4 Nf6 13.Bf3 0–0–0 14.c3 Rdg8 15.Bg5 Nd7 16.c4 h6 17.Be3 g5 18.d5 c5 19.dxe6 fxe6 20.b4 h5 21.Bxh5 Be5 22.Rb1 Rxh5 23.Qxh5 g4 24.f4 gxf3 25.Qxf3 cxb4 26.Rxb4 Bd6 27.Rb3 Rg3 28.Qe2 b6 29.Kh1 Rg6 30.c5 Nxc5 31.Bxc5 Bxc5 32.Qh5 Qg7 33.Qf3 Kb8 34.Qf7 e5 35.Qe8+ 0–1

Black won?