05 December 2014

Analyzing Variations

Lesson of the Week

My chess students range from beginners struggling to remember how all the pieces move to several of the top local scholastic competitors. In a club for beginners this week, I worked with most of the students individually on checkmate with queen and king against a lone king (see "Teaching Elementary Checkmates").

My other students--both those receiving individual lessons and those in groups--were presented with a variety of positions that might have occurred in actual games. A few were also shown a portion of a game from the 1969 World Championship between challenger Boris Spassky and Tigran Petrosian.

Many students saw two positions that might have resulted in the first match game between Louis Charles de la Bourdonnais and Alexander McDonnell (see "Three Fighting Draws" for the whole game).

Black to move
After 46.Nxe7
Could White have preserved the draw after 46.Nxe7 instead of the move he played in the game?

This variation might have led to the following position.

White to move

Can White prevent Black's pawn from becoming a queen?

Several students were shown the entire game Mayet -- Anderssen, London 1851.*

1.e4 e5 2.Nf3 Nc6 3.Bb5 Bc4 4.c3 Nf6 5.Bxc6 dxc6 6.O-O Bg4 7.h3 h5 8.hxg4 hxg4 9.Nxe5 g3 10.d4 Nxe4 11.Qg4 Bxd4 12.Qxe4 Bxf2+

The game may have ended here, or been played one move longer, or even all the way until checkmate.

White to move
After 12...Bxf2+

Those who were shown this game went through it repeatedly, looking for improvements. First, efforts were made to find where White's position became hopelessly lost and to suggest alternatives. Then, efforts were also made to find improvements for Black.

One group and several individuals were shown the final portion of Spassky -- Petrosian 1969.

Spassky,Boris V -- Petrosian,Tigran V [D41]
World Championship 27th Moscow (5), 23.04.1969

1.c4 Nf6 2.Nc3 e6 3.Nf3 d5 4.d4 c5 5.cxd5 Nxd5 6.e4 Nxc3 7.bxc3 cxd4 8.cxd4 Bb4+ 9.Bd2 Bxd2+ 10.Qxd2 0–0 11.Bc4 Nc6 12.0–0 b6 13.Rad1 Bb7 14.Rfe1 Rc8 15.d5 exd5 16.Bxd5 Na5 17.Qf4 Qc7 18.Qf5 Bxd5 19.exd5 Qc2

White to move

The most important element in this position is White's passed d-pawn. In Chess.com's Chess Mentor, this position is presented with guidelines for handling such pawn. I communicated these ideas to the students.

1) control the square in front of the pawn
2) trade off minor pieces
3) keep the queens on the board to prevent the defending king's activity
4) keep at least one rook

The player defending against such a pawn, of course, hopes to trade queens, blockade the pawn with a minor piece, and activate the king. The Chess Mentor lesson focuses on White's side of things in this struggle and does not elucidate the defensive ideas.

20.Qf4 Qxa2 21.d6 Rcd8 22.d7 Qc4 23.Qf5 h6 24.Rc1 Qa6 25.Rc7 b5 26.Nd4 Qb6 27.Rc8

The Chess Mentor lesson ends here.

27...Nb7 28.Nc6 Nd6 29.Nxd8 Nxf5 30.Nc6 1–0

*The Oxford Encyclopedia of Chess Games (1981) presents this game as Berlin 1859 with the source as The Chess Monthly (1882). In that publication, however, it is stated that the game was played during the International Chess Tournament, London 1851. Mayet and Anderssen did not play each other in that tournament, but all of the participants played many non-tournament games with one another during the course of the event.


  1. In the K+P ending at the start of the this article, it's much easier to calculate if you know what square White's king needs to be shooting for to secure the draw. If you know that, then it's a simple matter of counting.

    When I was the age of your students, I would have tried to calculate it all out, move by move (he goes there, then I go there, then he goes . . .")

    At some point the picture would have gotten blurry and I would have had to start over--or maybe just give up and play by instinct.

    Sometimes it seems like chess is all about building up shortcuts and prior knowledge. Now I know exactly what to look for when trying to figure that endgame out. Back then? I would have been clueless.

    1. "Building up shortcuts"! I think that I'll use that phrase, Dave. Thanks. I always enjoy your perspective.

      I hope that by putting positions such as this one in front of students, they will become habituated towards concrete analysis and calculation, as well as developing their intuitive grasp of elementary endings.