Historical riddle: Hort vs. Fischer 1970

by Karsten Müller
7/29/2020 – Bobby Fischer obtained an astounding 18½ out of 23 score to win the 1970 Interzonal Tournament in Palma de Mallorca. In round 5, the American genius defeated Vlastimil Hort with black in an opposite-coloured bishops endgame, but it is not clear whether the ending was always winning or not! Endgame specialist Karsten Müller asks for your help.

Endgames of the World Champions from Fischer to Carlsen Endgames of the World Champions from Fischer to Carlsen

Let endgame expert Dr Karsten Müller show and explain the finesses of the world champions. Although they had different styles each and every one of them played the endgame exceptionally well, so take the opportunity to enjoy and learn from some of the best endgames in the history of chess.


Palma de Mallorca is the largest city of the autonomous community of the Balearic Islands in Spain. Also known as Palma, it hosted the last Interzonal tournament held as a single-section round-robin in 1970 — from 1973 onwards, the system was changed to two Interzonals.

Bobby Fischer was the star of the show, as he came from winning tournaments in Zagreb and Buenos Aires with incredible performances. The tournament ran from November 9 to December 12, and saw Fischer obtaining an astounding 18½ out of 23 score, winning 15 games and losing to Bent Larsen in round 9. Fischer collected 10½ points in the last 11 rounds, scoring seven consecutive wins to end the tournament.

This would be the start of an amazing run that led him to challenge Boris Spassky for the World Championship title in Reykjavík. As we all know, he then became the 11th world champion. The Interzonal in Palma turned out to be Fischer’s last tournament appearance, as he only played matches from then on.

But one endgame has remained mysterious to this day. Fischer defeated Vlastimil Hort with black in an opposite-coloured bishops endgame. Thus, the riddle: was the American genius always winning, or could Hort have defended?

Endings with pure opposite-coloured bishops have a very large drawish tendency. But when rooks are there, then the guideline from the middlegame that the position favours the attacker gets more importance. But as the winning potential is already very reduced it is a borderline case even for modern engines.

So your job is to answer the following questions: was the endgame always winning, or did both sides make mistakes? If so, where was Hort's last mistake?


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.

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Karsten Müller, born 1970, has a world-wide reputation as one of the greatest endgame experts. He has, together with Frank Lamprecht, written a book on the subject: “Fundamental Chess Endgames” in addition to other contributions such as his column on the website ChessCafe as well as in ChessBase Magazine. Müller's ChessBase-DVDs about endgames in Fritztrainer-Format are bestsellers. The PhD in mathematics lives in Hamburg, where he has also been hunting down points for the HSK in the Bundesliga for many years.
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Stefan64 Stefan64 8/6/2020 09:42
Fischer won his game in Palma vs Panno by forfeit. That shouldn’t count. He would most likely have won that one too playing the white pieces.
Karsten Müller Karsten Müller 7/31/2020 08:37
Malfa: Yes good point. 57.g5 should indeed draw.
wb_munchausen wb_munchausen 7/31/2020 12:04
Speaking of Fischer, Dr Grande just put out a video about Fischer this week:


Interesting, though not everyone would agree with what is said.
brian8871 brian8871 7/30/2020 09:28
Hort was playing from behind through most of the game. In the full game, he was already in trouble starting at move 8. When it goes from "behind" to "hopelessly lost" is a difficult question to answer, but I know I wouldn't have wanted to be in his chair.
Karsten Müller Karsten Müller 7/30/2020 07:39
ays020209: Your suggestion 65.Rf1 Ra7 66.Rf8 is met by 66...e4 67.Kxg4 Re7 68.Rh8 Kf6 69.Bf5 Rg7+ 70.Bg6 Ke5 71.Re8+ Kd4 and Black should be winning in the long run.
ays020209 ays020209 7/30/2020 06:19
65..Ra7 Rf8
ays020209 ays020209 7/30/2020 06:18
But instead of 66 Kg4 white can play Rf8
Karsten Müller Karsten Müller 7/30/2020 11:27
Yes I agree. In also think that Fischer was the best player of all time. And indeed one point is:
"In der Zeit von 1970-1972 waren seine Ergebnisse die besten aller Zei ten. Er ver lor nur 5 Partien (wenn die
kampflose Niederlage in der zweiten Partie gegen Spasski in Reykjavik nicht mit gezählt wird) von 102 Partien – inklusive dem Interzonenturnier, dreier Kandidatenzweikämpfe und dem Weltmeisterschaftskampf. Er gewann zwei Kandidatenzweikämpfe 6-0 und führte die Weltrangliste vor dem Match in Reykjavik an und zwar unglaubliche 125 Elopunkte vor Weltmeister Spasski."
malfa malfa 7/30/2020 11:11
Black's central pawn mass won the game, so what about playing g4-g5 at some early point in order to weaken its basis and to keep its dynamic potential at bay?
Davidx1 Davidx1 7/30/2020 10:17
He invented the Fischer chronological system: a proof of genius.
Although the 1960s were dominated by that abstract entity that was the "Soviet school", Bobby's results in the 70-72 period are superior to those of Kasparov and Carlsen.
Karsten Müller Karsten Müller 7/30/2020 09:06
ays020209: Your improvements come too late. 65.Rf1!? is certainly better, but should also be losing after 65...Ra7 66.Kxg4 Ra4+ 67.Kh3 (Let's Check evaluation is about -2.7) 67...Bf4 and in the long run Black should be winning. And in case of 72.Re6 Black wins after 72...Rg1+ (Let'c Check evalutions before already over +10). Please search earlier for improvements!
ays020209 ays020209 7/30/2020 07:03
And then on 72nd move he should have played Re6 not Kf5
ays020209 ays020209 7/30/2020 07:02
White lost in move no. 65 He should have played Rf1 not K*g4