Riddle: Was Flohr vs Botvinnik sound?

by Frederic Friedel
7/24/2020 – 1933, Moscow. Michael Botvinnik had just won the USSR Chess Championship. A match was arranged between him and one of the top players at the time, Czechoslovakian Champion Salomon Flohr. The 12-game match was drawn, after Flohr took an early lead. In one of his games he showed the chess world how to force a win in the 2B vs 2N endgame. But did he really, or did Botvinnik simply misplay it? Can you help endgame specialist GM Karsten Müller answer this question?

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In 1933 Mikhail Botvinnik won the USSR Chess Championship. Soon after that, a match was organised between the new Soviet champion and one of the other top players at the time. Salomon Mikhailovich Flohr was born in a Jewish family in what is today Ukraine. His parents were killed in a massacre during World War I, and he and his brother fled to the newly formed nation of Czechoslovakia. Flohr took up chess, became champion of Czechoslovakia in 1933 and 1936, and was considered a leading challenger for the World Championship.

The match against Botvinnik was scheduled over twelve games, six to be played in Moscow and six in Leningrad (Saint Petersburg). Flohr was considered the favourite, and the first half of the match seemed to confirm this assessment. Flohr wrapped up the first half with a +2, but Botvinnik fought back in Leningrad, winning two games to leave the match tied 6:6.

If you want to see how a match like this was staged and how it drew crowds in the USSR, take a look at the following video:

Flohr won the first game with black, and outplayed Botvinnik in game six with the white pieces. In his book "How to Play Chess Endings", Eugène Znosko-Borovsky says that the game contained an extremely instructive ending, which well demonstrates the concentrated power of the two bishops, and the helplessness of the two knights against them — they move in various directions on the board, without any coordination. "The slow pressure exercised by the bishops against a closed position is demonstrated after 40...Ne8. The bishops have ample space, whilst the knights are confined to the first three ranks. Worse still, they can obtain no strong points in the centre, which is frequently the case against two bishops, which can dominate the whole board. The knight on d7 is particularly badly placed: as soon as it moves, the opposing bishop is played to c8, attacking the b-pawn, which in turn cannot move without weakening the a-pawn: we see how difficult the situation is for Black." 

Mikhail Botvinnik and Salo Flohr during their match in Moscow, in 1933

This brings us to today’s riddle: In this famous endgame, considered singularly instructive in the way to play a bishop pair against two knights, did Flohr show the chess world how to convert the superiority of the bishops? Or did Botvinnik misplay the ending? One thing is clear: the ending is very deep.

[Event "Botvinnik - Flohr"] [Site "Moscow / Leningrad RUS"] [Date "1933.12.05"] [Round "6"] [White "Salomon Flohr"] [Black "Mikhail Botvinnik"] [Result "1-0"] [ECO "E38"] [Annotator "Karsten Müller"] [PlyCount "137"] [EventDate "1933.11.28"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2 c5 5. dxc5 Na6 6. a3 Bxc3+ 7. Qxc3 Nxc5 8. f3 d6 9. e4 e5 10. Be3 Qc7 11. Ne2 Be6 12. Qc2 O-O 13. Nc3 Rfc8 14. Be2 a6 15. Rc1 Ncd7 16. Qd2 Qb8 17. Nd5 Bxd5 18. cxd5 Rxc1+ 19. Qxc1 Qd8 20. O-O Rc8 21. Qd2 Qc7 22. Rc1 Qxc1+ 23. Qxc1 Rxc1+ 24. Bxc1 Kf8 25. Kf2 Ke7 26. Be3 Kd8 27. Ke1 Kc7 28. Kd2 Nc5 29. b4 Ncd7 30. g3 Nb6 31. Kc2 Nbd7 32. a4 Nb6 33. a5 Nbd7 34. Bc1 Kd8 35. Bb2 Ne8 36. Kd2 Nc7 37. Ke3 Ke7 38. Bf1 Nb5 39. h4 Nc7 40. Bh3 Ne8 41. f4 {[#]The old riddle of Flohr vs Botvinnik One of the most instructive endings in the constellation bishop pair against two knights is the following famous classic. At first sight it seems that Flohr has won easily due to the superiority of his bishops. But closer inspection shows that matters are very deep:} f6 42. Bf5 g6 43. Bh3 h6 44. Bc1 Ng7 45. fxe5 dxe5 46. Kf3 h5 47. Be3 Kd6 48. Bh6 Ne8 49. g4 hxg4+ 50. Bxg4 Nc7 51. Be3 Nb5 52. Ke2 Nc7 53. Kd3 f5 54. exf5 gxf5 55. Bxf5 Nxd5 56. Bd2 N7f6 57. Kc4 Kc6 58. Bg6 b5+ 59. Kd3 Ne7 60. Be4+ Ned5 61. Bg5 Nh5 62. Bf3 Ng3 63. Bd2 Kd6 64. Bg4 Nf6 65. Bc8 Kc6 66. Be1 e4+ 67. Kd4 Ngh5 68. Bf5 Kd6 69. Bd2 {Your job is: was the ending winning from the beginning or did both sides commit several mistakes on the way ?} 1-0

We need your help

Please send any analysis you come up with to me at the following email address: Karsten Müller. You may also like to use more powerful engines to assist you in your efforts. Fat Fritz, for instance, goes for some unconventional continuations and surprises. Dr. Müller will evaluate your submissions and discuss them with you.

In case you are not familiar with our replay board (above), please note that there are a large number of functions you can use to understand the game and the moves. Just an engine (fan icon) and it will help you to analyse. You can get multiple lines of analysis by clicking the + button to the right of the engine analysis window. The "!" key, incidentally, shows you the threat in any position, which is incredibly useful in the case of unclear moves.

There is one more thing you can do. It is a lot of fun, but also a serious challenge: Click on the rook icon below the notation window. This will allow you the play the above position against Fritz, at your level of playing strength (e.g. "Club Player"), right here on the news page. Note that your analysis, in which you can delete, move or promote lines, is stored in the notation as new variations. In the end you will find the game with your analysis in the cloud. So nothing is ever lost.


Editor-in-Chief emeritus of the ChessBase News page. Studied Philosophy and Linguistics at the University of Hamburg and Oxford, graduating with a thesis on speech act theory and moral language. He started a university career but switched to science journalism, producing documentaries for German TV. In 1986 he co-founded ChessBase.
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JNorri JNorri 7/26/2020 03:31
Magic and Rambus, the FIDE rules were changed as of 1.1.1985. Until then it was legitimate to castle rook first. I remember that particularly well, since to my eternal shame I invoked the rule (and had my opponent play ...Rf8) in a game played on... 1.1.1985. Luckily I lost the game.

But 1933 is of course a different matter.
Karsten Müller Karsten Müller 7/26/2020 10:49
Many thanks, Charles! Also 32...Nb6 looks like a mistake from the human point of view, but matters are very deep of course. What do the readers think?
CharlesSullivan CharlesSullivan 7/26/2020 02:24
Black did make subtle errors before the 41st move. Stockfish-11 suggests that Black still had good drawing chances after 31...Na4 32.b5 a5 33.b6+ Nxb6 34.Bd2 a4 35.Ba5 Nfd7 36.Kc3 Kb8 37.Kb4 Na8 38.Kxa4 Nc5+ 39.Kb5 Nb3 40.Bc3 Nc7+ 41.Kb4 Nc5 42.Bd2 N7a6+ 43.Kc3 Nc7 44.h4 h6 45.Kb4 N7a6+ 46.Kc4 Kc8 47.Ba5 Nd7 48.Bf1 b6 49.Bd2 Kb7 50.Bh3 Nf6 (+0.97).
Earlier still, LeelaChessZero thinks Black should gambit a pawn with 15...b5 16.cxb5 Nb3 17.b6 Qb8 18.Rd1 Nd7 19.Qd3 Nxb6 20.Qxd6 Nc4 21.Bxc4 Bxc4 22.Na4 Bb5 23.Nc3 Bc4 24.Kf2 Be6 25.Qxb8 Raxb8 26.Rd3 h5 (+0.43).
Karsten Müller Karsten Müller 7/25/2020 01:06
Good point! As Zoran Petronijevic, Albert Silver and KevinC all agree that Black is already lost at move 41 it does indeed make a lot of sense to ask, if Black was already lost at move 24. So what do you think?
vbac vbac 7/25/2020 11:45
My first question would be why do we begin the analysis on move 41? The 2B vs 2N begins at move 24, and black seems to do almost nothing during all that time. There weren't better ways to defend from moves 24 to 41? If the answer is 'no', then black is lost not at move 41 but at move 24.

If a game is won, there must be a mistake somewhere. If it's not after move 41, then it must be either between 24th and 40th or before that.

And thanks for the article, the game and the ending! Very enjoyable and instructive!
Karsten Müller Karsten Müller 7/25/2020 09:00
KevinC: Really great! Albert Silver has programmed a new neural network endgame engine and it also concluded that Black is lost after 41...f6?! but also lost in any case.
Rambus Rambus 7/25/2020 05:01
That's a heck of a lot of spectators for 1933! And one of them castles illegally, touching the rook first.
Magic_Knight Magic_Knight 7/24/2020 09:02
Interesting to see (in that video) that Flohr castled by moving his rook first and then the king. Guess that was allowed back in 1933?
KevinC KevinC 7/24/2020 06:59
I am not submitting a formal answer, but I just looked at that with an engine, and it looked won all the way. Flohr played almost perfectly per the computer.

There is also the matter of practical chess: Even if there is some deep draw hidden there, no human could possibly hold that with a strong player playing white. One would have to play too perfectly.