His wife, Bella, and their son, Igor, were still in the Soviet Union and had not been allowed to leave. Just months before the match against Mr. Karpov, Igor was conscripted into the Soviet Army, though he refused to serve and became a fugitive. He was eventually caught and imprisoned for more than two years.

The players met in Baguio City, the Philippines, in a title match that had elements of farce.

Among the Soviet team of trainers and support staff was Vladimir Zukhar, who sat in the audience with his gaze fixed on Mr. Korchnoi. After Mr. Korchnoi lost Game 8, Mr. Korchnoi protested Mr. Zukhar’s presence, insisting that he was a parapsychologist. Mr. Zukhar was moved to the seventh row, but his presence in the playing hall remained an issue. Before the start of 17th game, Mr. Korchnoi threatened to pummel him.

To ward off Mr. Zukhar’s effects, Mr. Korchnoi took to wearing dark glasses. Mr. Karpov protested that he could no longer see Mr. Korchnoi’s eyes and was distracted by the reflection.

After Mr. Korchnoi lost games 13, 14 and 17 with just one win to Mr. Karpov’s four, he began studying with two yogis. They tried to attend the games, but were met by protests by the Soviets and were eventually barred from the playing hall.

Mr. Korchnoi continued to fall behind, but then stormed back, winning games 28, 29 and 31. But Mr. Karpov won the 32nd game — and with it, the match.

A rematch in 1981 was not nearly as close — Mr. Karpov won, 6 to 2. A year later, Bella and Igor were allowed to emigrate.

Viktor Lvovich Korchnoi was born in St. Petersburg, then called Leningrad, on March 23, 1931. He grew up in poverty. His father taught Russian and literature; his mother taught piano. His parents divorced when Mr. Korchnoi was quite young and he went to live with his father, partly because his mother was too poor to support him. His father taught him to play chess when Viktor was 6.