Sousse Interzonal with the score of 15½/21 after Fischer withdrew; this placed him 1½ points ahead of the field. He then won his first-round match against Lajos Portisch by 5½–4½ at Poreč 1968. In Malmö, however, he lost the semifinal by 2½–5½ to Boris Spassky, who went on to win the title. In 1970 he shared 2nd in the Palma de Mallorca Interzonal, on 15/23, behind Bobby Fischer. He reached his top rank in the Elo rating system at the start of 1971, equal third in the world (with Korchnoi, behind Fischer and Spassky) with a rating of 2660. He then defeated Wolfgang Uhlmann by 5½–3½ at Las Palmas 1971. But then he lost the semifinal 0–6 at Denver to Fischer, who also went on to win the title. Larsen later claimed that his one-sided loss to Fischer was due in part to his condition during the match: "The organizers chose the wrong time for this match. I was languid with the heat and Fischer was better prepared for such exceptional circumstances... I saw chess pieces through a mist and, thus, my level of playing was not good." In 1973 he failed to advance from the Leningrad Interzonal; he tied for 5th–6th places with 10/17, with Karpov and Viktor Korchnoi winning. In 1976 he won the Biel Interzonal, but lost his 1977 Candidates' match, a rematch of their 1968 encounter, to Lajos Portisch by 3½–6½ at Rotterdam. In the Riga Interzonal of 1979, Larsen scored 10/17 for 7th place, and did not advance. Tournament dominance (1965–73) Starting in the mid-1960s, Larsen enjoyed a very successful run in major tournaments around the world, and he and Fischer became the two strongest players outside the Soviet Union. Larsen played in a lot of strong events, at least as many as any other top player, and repeatedly finished ahead of the top Soviet players. He won at Le Havre 1966 with 9/11, ahead of Lev Polugaevsky. At Santa Monica 1966, he placed third with 10/18, behind Spassky and Fischer. He won at Havana 1967 with 15/19, ahead of a strong group that included Mark Taimanov, Smyslov, Polugaevsky, Gligorić, and Miroslav Filip. He shared 2nd–3rd places at Dundee 1967 with 5½/8, behind Gligorić. At Beverwijk 1967, he was 4th with 8½/15 (Spassky won). At Monte Carlo 1967, he shared 3rd–4th with 6/9, behind Fischer and Efim Geller. He shared 1st–2nd at Winnipeg 1967 with