About Tigran Petrosian
Tigran Vardani Petrosian was a Soviet-Armenian chess grandmaster. The ninth World Chess Champion from 1963 to 1969, he was nicknamed "Iron Tigran" due to his almost-impenetrable defensive playing style, which emphasized safety above all else. Petrosian is often credited with popularizing chess in Armenia. It was in this tournament that Petrosian faced world champion Botvinnik for the first time. He won the World Championship in 1963 (against Mikhail Botvinnik), successfully defended it in 1966 (against Boris Spassky), and lost it to Spassky in 1969. He won the Soviet Championship four times (1959, 1961, 1969, and 1975). This attitude was illustrated by his result in the 1955 USSR Championship: out of 19 games played, Petrosian was undefeated, but won only four games and drew the rest, with each of the draws lasting twenty moves or fewer.
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