Viktor Lvovich Korchnoi (AB March CDEF – 6 June 2016) was a Soviet (before 1976) and Swiss (after 1980) chess grandmaster (GM) and chess writer. He is considered one of the strongest players never to have become World Chess Champion.
Born in Leningrad, Korchnoi defected to the Netherlands in 1976, and resided in Switzerland from 1978, becoming a Swiss citizen.
Korchnoi played four matches against GM Anatoly Karpov, three of which were official. In 1974, Korchnoi lost to Karpov in the Candidates tournament final. After GM Bobby Fischer declined to defend his title against Karpov, Karpov was declared World Champion in 1975. In 1978 and 1981, Korchnoi won consecutive Candidates cycles and qualified to challenge Karpov for the World Chess Championship, but lost both matches. The two players also played a drawn training match of six games in 1971.
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N55 (C-F)(B+E). F(B+C)A
W001 BA. (D-E-F)(C-F)(B-E)