The Russian Chess Federation says that legendary Soviet chess player Viktor Korchnoi has died at the age of 85.
Born in 1931 in what is now St. Petersburg, Korchnoi is considered to be one of the world's best chess players that never became a world chess champion.
He was a four-time chess champion in the Soviet Union, a five-time member of Soviet teams that won the European championship, and a six-time member of Soviet teams that won the Chess Olympiad.
He defected from the Soviet Union to the Netherlands in 1976.
Korchnoi played three matches against Russian grandmaster and former world champion Anatoly Karpov.
In 1974, Korchnoi lost the final of the Candidates Tournament to Karpov.
Karpov went on to become world champion in 1975, when American chess grandmaster Bobby Fischer refused to defend his title.
Korchnoi also lost world championship matches against Karpov in 1978 and 1981.
In 2006, Korchnoi won the World Senior Chess Championship.
For years, he was the oldest active grandmaster on the tournament circuit.
Based on reporting by Reuters, AP, AFP, and TASS