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.

Chess Endgames 14 - The golden guidelines of endgame play

Rules of thumb are the key to everything when you are having to set the correct course in a complex endgame. In this final DVD of his series on the endgame, our endgame specialist introduces you to the most important of these rules of thumb.


Karsten Müller is considered to be one of the greatest endgame experts in the world. His books on the endgame - among them "Fundamentals of Chess Endings", co-authored with Frank Lamprecht, that helped to improve Magnus Carlsen's endgame knowledge - and his endgame columns for the ChessCafe website and the ChessBase Magazine helped to establish and to confirm this reputation. Karsten's Fritztrainer DVDs on the endgame are bestsellers. The mathematician with a PhD lives in Hamburg, and for more than 25 years he has been scoring points for the Hamburger Schachklub (HSK) in the Bundesliga.


Rules for reader comments


Not registered yet? Register