Viktor Korchnoi

Viktor Lvovich Korchnoi (Russian: Виктор Львович Корчной, IPA: [vʲiktər ˈlʲvovʲɪtɕ kɐrtɕˈnoj]; 23 March 1931 – 6 June 2016) was a Soviet and later Swiss chess grandmaster 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 in 1980.

Korchnoi effectively played Anatoly Karpov three times for the World Championship. In 1974, he lost to Karpov in the Candidates Tournament final, and Karpov became World Champion after Bobby Fischer declined to defend the title. Then in the next two world championship cycles, 1978 and 1981, Korchnoi won the Candidates but lost the World Championship match to Karpov.

Korchnoi was a candidate for the World Championship on ten occasions (1962, 1968, 1971, 1974, 1977, 1980, 1983, 1985, 1988, and 1991). He was also four times a USSR Chess Champion, five times a member of Soviet teams that won the European championship, and six times a member of Soviet teams that won the Chess Olympiad. He played competitive chess until old age. At age 75, he won the 2006 World Senior Chess Championship and became the oldest person ever to be ranked among the world's top 100 players.