Lesson of the Week

Working with Pins

Lessons the past couple of weeks have featured positions where a pin may be exploited to gain material. Sometimes another tactic is needed to create a pin and win material.

This position occurred in an online game one year ago. Black found the correct tactic here, but later lost his way and threw away his queen. White then demonstrated that he had difficulty finding an easy checkmate.

Black to move

Bonus problems: find White's quickest rout to checkmate.

White to move

Here White missed a checkmate in one.

White to move

The Blind Squirrel

Although I prefer to win by grinding down my opponent to reach a winning endgame, in blitz I reveal aggressive tendencies that arose as a consequence of my first chess book. These aggressive tendencies have manifested themselves in playing 1.e4 almost exclusively for the past several months and playing the Ponziani whenever possible (despite Dave's sage advice). Naturally, playing 1.e4 means that I face the Sicilian Defense in a high percentage of games.

A blitz game against the Sicilian Defense this morning featured blunder after blunder. There is nothing unusual in that fact. Often in online blitz, both players appear bent upon losing. My pursuit of a flawed plan was met by improper defense. Finally, my opponent thought that he had a credible checkmate threat that wins material, but overlooked my best resource.

The worst of the blunders began with this diagram.

White to move

I played 17.Qh6??

17.Qf3 was best, while 17.exd6 was better than the move played.

Instead of the natural straightening out of his doubled pawns, my opponent sought to drive back the bishop.

17...c4??

The game continued 18.exd6  (18.f5 was better) 18...Qxd6? (Black has a slight advantage after 18...Qf6--the aggressively placed White queen should not be ignored) 19.f5

Black to move

I was proud of my decision to offer the bishop. 19...cxd3 loses quickly to 20.f6.

19...Kh8?

Perhaps the simple refutation 19...Rfb8, freeing f8 for the queen is not so easy for Black to see.

20.f6 Rg8 21.Be2

21.Rf4 was best.

21...Qe5 22.Rae1 Qxb2 23.Rf4

Black to move

23...Qc3??

Black is winning after 23...g5.

24.Qxh7+ 1-0

Black resigned.

Premature Resignation

In a game played via the ChessByPost app, my opponent resigned after what may have been a sub-optimal move. I spent a bit of time during several sessions stretched out over more than a day determining whether I wanted to pursue a particular course. I was uncertain of the merits of my plan. In the end, I decided to consider further before taking the next step. It was still possible to pull back and try something else.

Black to move

I played 44...Bd1+.

My plan was to meet 45.Kg3 with 45...Rf3+ 46.Kxg4 Rc6+ 47.Kh4 Rxc5 48.dxc5 Bxc2.

White to move

I thought that my bishop and king would be sufficient for the ending, but that it was still possible to go wrong. My opponent spared me the exercise and resigned after 44...Bd1+.

Postgame analysis with an engine reveals that I had two better moves: 44...Rf4 was best. I do not recall considering this move. 44...Kf7, which I considered, was better than the move played.

Vexing

My failure this morning is due to exhaustion, not my failure to understand the demands of the position. This endgame study attributed to Edward Lasker appears in the Encyclopedia of Chess Endings II (1985).* There it is the eleventh problem in the text and the solution is a simple matter of reaching a version of the tenth problem.

White to move

White's difficulty stems from the failure of the simple 1.Rh5 (or Ra5) due to 1...Rd7+! and stalemate threats. I spent some time with such futile efforts against the silicon beast before I stumbled onto 1.Kc5, the only winning move.

Problem number ten is simple:

White to move

*The second edition of this volume was released earlier this year, but I have not yet invested in the updated version and am using the first edition.

Lesson of the Week

In this position, I have misplayed the Benoni Defense and offered my opponent the opportunity to gain a decisive advantage. This game was played on US Chess Live in 2001. I found it looking through my databases for examples of certain common pins.

Opponent -- Stripes
USCL 13.01.2001

1.d4 Nf6 2.Nf3 c5 3.d5 e6 4.c4 exd5 5.cxd5 d6 6.Nc3 g6 7.e4 Bg7 8.Bg5 Bg4 9.Bb5+ Nbd7 10.h3 Bxf3 11.Qxf3 O-O

White to move

11.O-O

White missed the win, and after 12...Ne5 Black began to solve his self-imposed problems and went on to win.

Find the move that White should have played. As a bonus for readers of this blog, identify Black's critical error leading to the diagram position.

Discovery

This position did not occur over the board, but was suggested in the notes to Nisipeanu -- Georgiev, Bled 2002. The notes are in Chess Informant 86/344. The game itself was drawn, but the annotators suggested a line beginning at 20.Nd4 (instead of 20.Nf4 as played in the game) that appears to offer White prospects of advantage.

White to move

26.Nb5! threatens to penetrate Black's queenside with the knight, while also unleashing a discovered attack on the light-squared bishop, followed by the rook's penetration to the seventh rank. Black would have been forced to choose which invader he prefers to contend against. First, though, he may exchange some pawns on the kingside with hopes of activating his rook there.

Remove the Defender

This position arises in the second game of the first issue of Chess Informant in 1966. It is a wild game.

White to move

A Simple Pin

Lesson of the Week

As the 2014 Washington State Elementary Chess Championships have concluded, most school clubs have come to an end for the school year. Nonetheless, a few clubs and my class at a home school resource center continue through May. This week, students are presented with a tactical exercise that strong players can solve in a second.

The knights protect each other nicely, but Black's bishop is unprotected. In addition, two White pieces target the f7 square.

White to move

One Strong Move

But, is it the strongest?

In the game of chess, players seek to create problems for their opponents to solve. When the opponent falters, and advantage is gained. Often this advantage may be converted into victory.

This position arose from a line in the Smith-Morra Gambit in which White offers an additional pawn in the manner of the Danish Gambit. The first time that I remember playing it was during some chess in the bowling alley. We were bowling and making our moves on the chessboard while the other was knocking down pins. This gambit line never worked against Kevin Baker a second time and it has failed against many internet opponents. Sometimes it succeeds, though.

White to move

After 19...Rfd8

I played 20.Bxg7!

Clearly, my opponent's 20...Kxg7 represents a failure to solve the problem that I set. 20...f5 is the obvious effort to refute White's plans. Then, one of the minor pieces is lost. After 20...f5, does White have compensation for the minor piece and two pawns?

Was 20.Nxh6 the correct move for White? Did White have some other way of applying pressure to Black's position?

There is no time to waste.

Is this Tactic Common?

An easy blitz win this morning reminded me of several other games: my highest rated correspondence win on Chess.com, the first round of the 2009 Washington Open, and dozens of other blitz games. Although some elements of the position differ in each, the basic elements are there over and over again.

White to move

The key elements of the position: Black's knight is pinned, the d-file is open and both queens stand there, a knight is poised to jump to d5, which Black's c-pawn does not prevent.

This game continued 10.Qxd8 Rxd8 11.Nd5 Rd6 12.Nxc7 winning a pawn. This morning, my opponent opted not to save the rook with 12...Rb8.

A similar position appeared in the first round of the 2009 Washington Open.

White to move

I was disappointed that I managed only a draw in that game, but the event itself is notable because I finished with no losses and the event lifted my USCF rating into A Class.

In a memorable correspondence game on Chess.com, the key elements of the position appeared again.

White to move

In this game I played 10.Nd5 which may be more accurate than 10.Qxd8. I usually see this sort of position in blitz.

Bailing Out

During a little more exploration of an obscure variation (the Ragozin), I found a game where Karel Opočenský (1892-1975) disliked the line he had chosen in this opening against Jindrich Engel, Bad Sliac 1932.

Black to move

Did Black have anything better than 15...Rxg2+ and the following forced repetition?

A Typical and Uncommon Position

Although this position contains several common elements that arise in the French, it appears in only thirteen games in the ChessBase online database. It also cropped up in my second blitz game this morning.

The position arises in the Tarrasch after 1.e4 e6 2.d4 d5 3.Nd2 Nf6 4.e5 Nfd7 5.f4 c5 6.c3 Nc6 7.Ndf3 cxd4 8.cxd4 f6 9.Ne2 Bb4+ 10.Kf2 fxe5 11.fxe5 O-O*

White to move

My opponent played 12.Kg1 and I won the game in 47 moves. He lost a pawn on move 33 and lost a piece to a knight fork on move 44.

Black's immediate target is e5. If it were Black's move, the pawn could be taken as one of the defending knights is pinned. The locked center with targets on d4 and e6 is typical of the French Defense. White's king on f2 is a common maneuver. White's bishops have more scope even though neither has moved.

My opponent stepped out of the pin.

A) 12.Kg3 was played in three games. That was the end of one game--a draw was agreed. It was the only game between masters. 12...Ne7 and 12...Nb6 were played in the other two games.

12...Ndxe5+ has not been tried. 12.Kg3 might be regarded as an error.

B) 12.Be3 was played in three games. All continued 12...Ndxe5 13.dxe5 Nxe5

White to move

Skripchenko -- Maric, New Delhi 2000 continued 14.Qb3 b6 15.Rd1 Qe7 16.Kg1 and was drawn in 42 moves.

14.Bd4 was played in the other two games.

Black won a long battle in Matsura -- Cordova, Sao Paulo 2006 that continued 14...Nc6 15.a3 Bd6.

A draw was reached after a few moves in the more recent Kumaran -- Ram, Chennai 2013: 14...Qh4+ 15.Ng3 Nxf3 16.gxf3 e5 and drawn three moves later. 16...e5 may be inaccurate.

Black certainly has the better game after 12.Be3, which may be regarded as dubious at best.

C) 12.a3 was played in three games.

A correspondence game continued 12...Qh4+ 13.Kg1 Rxf3 14.gxf3 Ndxe5

White to move

White should have been happy to escape this correspondence game with a draw.

12...Ndxe5 was played in the other two games.

Black seems to have found frustration in Popov -- Danin, Smolensk 2005, which continued 13.dxe5 Bc5+ 14.Ke1! Nxe5 15.Nxe5 Bf2+ 16.Kd2 Qg5+ 17.Kc2 Qxe5 18.Kb1

Black to move

After his long journey, the White king appears less vulnerable and White went on to win.

White also survived Black's early attack in Polgar,J -- Hernandez, Merida 2000. That game continued 13.axb4 Qh4+ 14.Kg1 Nxf3+ 15.gxf3 Rxf3 16.Ng3 Nxd4 17.Bg2

Black to move

White went on to win.

Black should have the better game after 12.a3, but in practice has failed to prove it.

D) My opponent's 12.Kg1 may be an error.

However, I missed the thematic 12...Ndxe5. Instead, I tried 12...Qb6. My opponent played 13.Be3

Black to move

13...Ndxe5 remains the correct move. Instead, move-by-move, I squandered my advantage and won only due to tactical errors by my opponent in the ending.

Searching the database for the position in the first diagram produces games where it appears that White should be okay. With optimal play by both sides, however, Black should have a clear advantage. White's pawn center is weak in part due to the vulnerability of the White king.


*Notation leading to the diagram position was added per a request in the comments below.

Power of Knights

Even after too much online blitz, I sometimes review a batch of my games. Sometimes I look at the openings and make efforts to refine my repertoire. If I improve the quality of moves I make in the beginning of the game before I start thinking, I may reach better positions. Sometimes I review the tactics that I missed.

My database software, ChessBase 11, easily guides me to master games that shared the opening that I fell into (or played deliberately). One of these games (Kallio -- Anastasian, Batumi 2002) caught my eye with its spectacular finish.

Black to move

32...h1Q 33.Rxg7+ Qxg7 34.Rxh1 Nb3+ 35.Kb1 Nbd2+ 36.Kc2+ (36.Kc1 appears to save the game) 36...Nc4 37.Qc6 (hastening the end) 37...Qg2 38.Kb3 Na5+ 0-1

After looking through these moves several times, then going back through the game as a whole, I returned to the diagram position and began to ponder.

I liked 32...Nb3+ and wondered why it was not as good as the move played in the game.

White has two choices.

1) If 33.Kb1, then 33...Ned2+ 34.Kb2 Nf3+ (here I first considered 34...Nf1 to aid the pawn's promotion) 35.Kxb3 Nxe1 36.Rxg7+ Qxg7 37.Qxh2. White has exterminated the promotion threat, but leaves Black a rook ahead.

2) If 33. Kd1, the position seems complex.

Black to move

Checking my ideas with an engine, I learned two things. First, my 32...Nb3 is superior to the move played in the game. Second, I failed to find the correct continuation from the second diagram. Perhaps you can do better.

Rescue

Lesson of the Week

Spring Break is next week and the 2014 Washington State Elementary Chess Championship is at the end of break. Most school chess clubs are coming to an end for the year.

This week's lesson is a position from the recent Candidates Tournament, which was won by Viswanathan Anand. Former World Champion Anand earned a rematch against Magnus Carlsen. Another former world champion, Vladimir Kramnik, had the strongest tie-breaks of the three who shared third place. He defeated his nemesis, Veselin Topalov, in round thirteen after losing to him in round six. Our problem position comes from Kramnik's win.

It appears that Kramnik's bishop is trapped.

White to move

Opening Inaccuracy

Chess is so deep and varied that even on the sixth move in a familiar line, one can reach new positions. Yesterday, I had the Black side of a Nimzo-Indian Defense that transposed into a somewhat obscure line of the Queen's Gambit Declined.

1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.Nf3 d5

4...c5 is the normal move in the spirit of the Nimzo-Indian Defense.

5.Qa4 Nc6 6.e3

6.Bg5 is almost as popular and is given in the first four lines of the Encyclopedia of Chess Openings. It may be of interest that in Chess Informant 10/600 Vladimir Sokolov judged 6.Bg5 as dubious, suggesting 6.e3. Perhaps 6.e3 is slightly more accurate than 6.Bg5. Even so, both moves have been played often.

Black to move

6...O-O appears to be the normal move here. My 6...Bd7 is the second most popular choice. Zoltan Gyimesi is the highest rated player who has played 6...Bd7 and he lost that game in a queen ending with most of the pawns remaining on the board and a nearly locked position.

It is hard to blame the opening for that loss. Nonetheless, the scoring percentage differences between 6...O-O and 6...Bd7 seem significant. White scores 55.6% over 411 games after Black castles. In the 55 available games with 6...Bd7, White's score jumps to 68.2%.

In my game, my position quickly grew poor with terrible piece coordination. My position was lost until my opponent blundered an exchange that led to an ending where I had a rook against a knight. All the pawns eventually came off and the game was drawn.

Is 6...Bd7 an inaccuracy, perhaps even an error? I think so.

6...Bd7 forces White's queen to move a second time due to the threatened discovery. 6...O-O steps out of the pin. Perhaps the queen then has less purpose on a4 and will be compelled to move again when Black's bishop is no longer a target.

Why is it an error? Does the bishop have a better square? It may. In games where Black castles, the bishop often goes to d7, but sometimes it goes to e6 or f5. In a few games, it takes up a position on b7. The major problem with 6...Bd7 is that it wastes time. Pieces should be placed on their best squares when they move for the first time. It is not clear in the diagram position where this bishop will be best placed. It is clear, however, that Black will castle kingside.