28 April 2022

Final Worksheet

My after school chess club started doing worksheets when COVID reached such numbers that we wanted to maintain social distancing during chess club, not allowing the children to crowd together for a lesson at the demo board. When we could again use the demo board, we continued with the worksheets. Today was the last club meeting this school year, so I created a special worksheet.

Three of these appeared on previous worksheets.

Find the correct move for White in each diagram. Draw an arrow showing the correct move. Answers are in order of piece value from weakest to strongest (and then most important).

1. Mate in one

2. Win material

3. Start an attack

4. Mate in two

5. Mate in five

6. Assure pawn promotion


20 April 2022

En Passant

In yesterday's after school chess club, I presented a position and conclusion to a game I had played earlier in the day. In a discussion about a different game on social media this morning, I mentioned this game again. IM Cyrus Lakdawala pointed out some similarities between my game and Aronin -- Smyslov, Moscow 1951, inquiring whether Smyslov's idea might have given my opponent drawing chances. Curiously, both games featured an en passant capture. In Smyslov's game en passant produced the kingside pawn structure that would have resulted in my game had my opponent chosen not to capture en passant.

Black to move
This position is completely even. But, here, my opponent blundered.

32...Rd8??

With the move came a draw offer, not my opponent's first such offer. Just about any other move that keeps the rooks on the board is equal, but the pawn ending is completely winning for White. Before exchanging rooks, I spent 38 seconds (a long think in a ten minute game) contemplating the pawn ending. I saw that my king has a route behind Black's pawns.

The Black king, in contrast, cannot penetrate to my side. My pawns control all points of entry.

However, Black does have a pawn break with f5 that can alter the pawn structure. As it happens this was a critical resource in Smyslov's game.

Central to my plan of penetrating with my king is that I am able to create a passed pawn on the h-file. Lev Aronin also gained a passed h-pawn against Smyslov. I knew my opponent could prevent my h-pawn from becoming passed, but that allows my king to enter via a shorter route.

34.Rxd8 Kxd8 35.h4

Black to move
As I explained in the discussion with Cyrus, if I had not found a route for my king, I would have played 35.h3, forcing an exchange of pawns.

Playing the pawn two squares instead of one offers Black the choice of capturing it as if it had moved only one square, or letting me have a passed h-pawn. That is en passant (capturing the pawn in passing), the rules for which was part of my lesson in yesterday's chess club.

35...gxh3+

White to move

36.Kxh3 Ke7 37.Kg4 Ke6 38.Kg5 f6+ 39.Kg6 Ke7 40.g4 Ke6

White to move
The maneuvering for opposition and outflanking is vital in this position. It is not yet a technique this group of students knows well. Teaching them how to do so was not the object of the lesson. Rather, I simply wanted to show them the process and use another day to teach them how to do it. Learning the en passant rule was the most important lesson for many of the children.

41.c4 Ke7 42.c5

Securing the queenside was not necessary but having already thrown away a decisive advantage to reach an equal endgame, I was not willing to allow any complications.

42...Ke6 43.g5 fxg5 44.Kxg5 Kf7 45.Kf5 Ke7 46.Kxe5 Kf7 47.Kd6 Kf6

White to move
48.e5+ Kf7 49.Kd7 and Black resigned.

Aronin -- Smyslov, Moscow 1951 is the first ending in Vasily Smyslov: Endgame Virtuoso, trans. Ken Neat (1997).

White to move
45.g4

Smyslov writes that his opponent was sure of victory when he played this move.

45...hxg3

No, Aronin was not unfamiliar with en passant. Rather, he saw, correctly, that he could get a passed h-pawn.

46.fxg3 g4!

Smyslov writes, "A paradoxical decision, since the h-pawn becomes a passed pawn" (7).

47.h4

Black to move
Compare the kingside pawn structure here to my game after 35.h4

47...c5 48.Ke2 Kh7

This was the move that caught my eye while looking at Cyrus Lakdawala's analysis of Aronin -- Smyslov.

White to move
49.Kd3 Kh6 50.c3 a5 51.cxb4 axb4 1/2-1/2

Smyslov notes that 52.Kc4 is met by f5!

A key pawn break, mentioned above.

53.Kd3 f4 54.gxf4 exf4 55.Ke2 Kh5 56.e5 Kg6 and Black's king stops White's two passed pawns. Black's pawns are another matter.

Analysis Diagram

The discussion with Cyrus hinged on the differences on the queenside between my game and Smyslov's textbook demonstration of a drawing resource. Instead of capturing en passant, my opponent might have tried 35...Ke7

White to move
Play might have continued 36.Kf2 Kf6 37.Ke3 Kg7 38.Kd3 Kh6 39.Kc4

Cyrus pointed out, as did Smyslov, that Aronin could not play this move.

39...Kg6 40.Kc5

Black to move
Black can strike with 40...f5 or wait with Kh7.

40...f5 41.exf5 Kxf5

White to move
42.Kc4 is the only winning move.

Alternately 40.Kh7

White to move

White loses with 41.Kb6, which was part of my calculation when I opted to exchange rooks. However, 41.Kd6 wins. I would like to believe I would have found the correct move here had my opponent been enough of a student of Smyslov to put me to this test. Instead, by capturing en passant, I was given an easy finish. What might have been, on the other hand, is a source of chess pleasure

13 April 2022

Rook and Bishop Checkmate

Lesson of the Week

Most of my students this week are receiving instruction in checkmate patterns employing rook and bishop. Most of the exercises feature a queen sacrifice to expose the king. I have drawn several positions from Victor Henkin, 1000 Checkmate Combinations, trans. Jimmy Adams and Sarah Hurst (2022) and several more from Georges Renaud and Victor Kahn, The Art of the Checkmate, trans. Jimmy Adams (2015). I also culled some positions from databases. For discussion of these books, see "Learning Checkmate (Or Teaching It)" and "Two Old Books (and one new)".

This position is published in my own Checkmates and Tactics (2019).

White to move. Mate in three.
This mate in five has stymied many of the students.

White to move
This mate in three is easier.

White to move
Morphy's famous queen sacrifice against Louis Paulsen in 1857 leads a series of imitators offered in Renaud and Kahn, The Art of the Checkmate.

Black to move
Samuel Boden followed Morphy's example to get a winning attack with multiple checkmate threats from this position.

Black to move

In all, I prepared 18 positions, but no students have seen them all. Some of my younger beginners received a worksheet with three mate in one and three mate in two.

This position was on a worksheet for older or more advanced students in my after school chess club. It comes from a game I played against Crafty on the Chessimo iPad app.

White to move
How many can you solve?





10 April 2022

Sandpoint Chess Tournament

Sandpoint, Idaho is a small community of less than 9000 residents that sits on the north end of Lake Pend Oreille. About thirty years ago, Lou Domanski, an A-Class chess player, moved there after retirement and developed some chess programs, including an annual chess tournament. Organized by Sandpoint Parks and Recreation, the event draws 20-50 chess players of all ages, an impressive turnout for a community this size.

In 2009, I was asked by a local who had been bringing his daughter to youth events that I ran in Spokane, whether I could run the event as Lou Domanski was no longer able to do so. It has become an event that I look forward to every April. A 75-90 minute drive from my home, depending on the weather, Sandpoint is a terrific community to visit.

I sometimes play in the event to reduce byes in the open section. One year, I played because I was looking for revenge after losing to Savanna the previous year. I had coached her a bit prior to her success as Idaho Girl's Co-Champion, which earned her a trip to Susan Polgar National Invitational for Girls, where she finished 9th. At the next event where we faced each other, she beat me again. The final moves of that game found their way into Forcing Checkmate (2017), which can be purchased through Amazon. For a few years as she finished school, Savanna regularly won the open section. I beat her the second time I played in the event, but lost to another player and still finished in 2nd place.

Coming back after two years without the event due to COVID, yesterday's event was small. There were five players registered for the open section, and fifteen in the other two. I opted to play so no one would get a bye. It gave us a round robin, albeit paired via Swiss System rules.

In the first round, I played the horrid 5...a6 from this position.

Black to move
My opponent punished the error and my position grew worse with further errors. However, when my opponent gave me a free piece with 15.Bxh7+, I clamored back into the game and eventually won.

Round two found me playing the risky and inaccurate 4.c3 in the Italian Two Knights

White to move
Play continued 4...d5 5.exd5 Nxd5 6.O-O Bg4 7.d4 e4?

White to move
After this error, I was able to take control of the game.

In round three, I gained a nice position from the Nimzo-Indian Defense and finished the game with a nice move here.

Black to move
Round four gave me an opportunity to show that Damiano's Gambit is a clear win for White, but I threw it away.

1.e4 e5 2.Nf3 f6?! 3.Nxe5 fxe5?

3...Qe7

4.Qh5+ Ke7 5.Qxe5+ Kf7 6.Bc4+ d5 7.Bxd5+ Kg6

White to move
8.Qg3+

This move is not best. 8.h4 presents Black with unsolvable difficulties.

8...Qg5 9.Qxc7 Ne7

White to move
This position was not new to me. I had it earlier this year in a rapid game on Lichess. It led to my only loss with Damiano's Gambit.

10.Qd6+??

From winning to equal. 10.h4 was the correct move.

10...Kh5

On Lichess, my opponent answered 10...Qf6, and after 11.e5??, I went from equal to losing.

11.e5 Bg6 12.Nc3??

Hunting for checkmate, I am blind.

12...Bxd6-+

I should have lost this game, but my opponent returned the gift of the queen three moves later.

My last round opponent is fairly new to active play and was eager for resources to develop his game. We had a nice conversation.

I quickly gained the upper hand with Black after the opening moves 1.e4 c5 2.Bc4 e6 3.h4 Nc6 4.c3 Nf6 5.Qe2 Be7 6.Nf3 d5

White to move
The annual Lou Domanski Chess Festival is friendly unrated competition that I run in accordance with USCF rules, sans clocks until the last 20 minutes of each one-hour round and no expectation of scorekeeping. Although my play was less than stellar, it was a good day. I enjoyed seeing again and playing some of the regulars at this event. It was a nice road trip, too. 




 

05 April 2022

Study by Johann Behting

When I posted this position two days ago on Facebook, it reached thousands more people than is usual for my high-performing posts, but elicited very replies with the correct move. There were responses, but most failed to observe the critical move--the only one that maintains a winning advantage.

White to move

According to Harold van der Heijden, Endgame Study Database VI, the study was published in Rigaer Tageblatt, a Riga newspaper. The composer is Johann Behting (1856-1944). His brothers, Karl and Robert, also published studies. When I encountered* this study in The Manual of Chess Endings by Sarhan Guliev on Sunday, credit was given to Karl and Johann with a date that was clearly incorrect (14). Guliev has 1984, while van der Heijden has 1894. The one in Guliev is one move earlier. Both appear in Endgame Study Database VI.

White to move
I contemplated my solution while eating breakfast, then set it up on my iPad to play against Stockfish. Although 1.Ke4 looked forcing, I could not see clearly to the end and opted to push a pawn first, instead--the wrong pawn, it turns out. Nevertheless, I prevailed against the engine.

1.f7 Ke7 2.Kf3!

As in the first position presented above, this move is the only one that wins.

2...c6 3.Kf4! c5 4.Ke4!

White moves to this square only after Black's c-pawn has advanced to c5, although it also can be played before advancing either White pawn. The computer's line reaches the same position that I did at move 8 (below).

4...Kf8 5.Kf5

Threatens checkmate.

5...Kg7 6.Ke5 d3

White to move
7.Kd6! d2 8.Ke7 d1Q 9.f8Q Kg6

Every move I've played after the first has been an only move.

White to move

I did not get the sense that my play from this point was the best, although it was good enough. After two more efforts from the beginning on my iPad, I spent some time evaluating the first effort on my computer.

In my second effort against Stockfish on the iPad, I started with the e-pawn, hence reaching the position in the other study after one move.

1.e7 Kf7 2.Kf3 c6 3.Kf4 d3

White to move
Stockfish chose the longest line to checkmate, I thought, but this choice made the rest of the exercise too routine. According to tablebases (the iPad app does not access these), both 3...d3 and 3...c5 lead to mate in 16. Only 3...c5, however, tests a human's skills above an elementary level.

On the third effort, I helped Stockfish a bit (switching sides) to get a chance to play the critical line against the app.

3...c5 4.Ke4 Ke8 5.Kd5 Kd7

White to move
6.Kc4! Ke8 7.Kxc5 Kd7

Here, 7...d3 strikes me as more testing. 8.Kd6 d2 9.Ke8 mates with a pawn, and concludes as in the solution given by Guliev.

8.Kxd4

The rest is simple.


*Note: After starting this post, I discovered that I had previously written about this study in "Two Endgame Compositions" (2016). Questions that I had then, I still have.