Henrique Mecking won the Petropolis Interzonal (1973) with Geller, Polugaevsky and Portisch in a shared second place. But only three players from Petropolis could go to the 1974 Candidates matches, and a playoff was necessary. It took place in Portoroz, Yugoslavia (Slovenia) in September. The ultimate goal was to select a challenger for Robert James Fischer, the World Champion.
The Hungarian Portisch started the four-way round robin with a disadvantage, as he had the lowest Sonneborn-Berger score in the interzonal. In the event of a three-way tie, or a tie for second place, he would be eliminated. His two rivals were also of the same nationality. The suggestion was made that the order of games be arranged so that the Soviet masters would always play each other first. Portisch protested. He trusted his opponents’ sportsmanship and with reason: during the course of the play, Geller and Polugaevsky won against each other in turn.1 In Geller vs Portisch, 1973, Geller (who had better SB score in the interzonal) erroneously marked the time control on the score sheet at move 84, and lost on time.2
Portoroz, Yugoslavia (Slovenia), 5-21 September 1973
Geller was thus eliminated. Mecking, Portisch and Polugaevsky joined Anatoly Karpov, Viktor Korchnoi and Robert Eugene Byrne from the Leningrad Interzonal (1973) for play against Tigran Vartanovich Petrosian (qualified as losing finalist in 1971) and Boris Spassky (qualified as ex-World Champion in 1972) in the following year's matches:
Elo 1234 1234 1234 Pts
1 GM Portisch 2650 **** 11˝˝ ˝1˝˝ 5˝
2 GM Polugaevsky 2625 00˝˝ **** 110˝ 3˝
3 GM Geller 2605 ˝0˝˝ 001˝ **** 3
Spassky - Byrne Candidates Quarterfinal (1974)
Petrosian - Portisch Candidates Quarterfinal (1974)
Karpov - Polugaevsky Candidates Quarterfinal (1974)
Korchnoi - Mecking Candidates Quarterfinal (1974)
All three qualifiers from Petropolis were eliminated in the first round matches.
Dates were provided by User: Chessical from the book World Championship Interzonals, Leningrad-Petropolis, 1973 by Robert Wade, Leslie Stephen Fraser Blackstock and Alexander Kotov (Batsford, London 1974), pp. 277-281.
1) Selected Games of Lajos Portisch by Egon Varnusz (Batsford, London 1979) p. 159. 2) Wade's book.
Original collections: Game Collection: Interzonals 1973 play-off: Portoroz by User: capybara and Game Collection: Portoroz Interzonal Playoff 1973 by User: Tabanus. Thanks to User: OhioChessFan for improving the English.