Chess right of a deposed champion to a rematch, and the next champion, Armenian Tigran Petrosian, a player renowned for his defensive and positional skills, held the title for two cycles, 1963–1969. His successor, Boris Spassky from Russia (champion 1969–1972), won games in both positional and sharp tactical style. The next championship, the so-called Match of the Century, saw the first non-Soviet challenger since World War II, American Bobby Fischer, who defeated his Candidates opponents by unheard-of margins and clearly won the world championship match. In 1975, however, Fischer refused to defend his title against Soviet Anatoly Karpov when FIDE did
Bobby Fischer brows, panic would overwhelm their nervous systems. Errors would creep in. Calculations would go awry. There was talk among grandmasters that Fischer hypnotized his opponents, that he undermined their intellectual powers with a dark, mystic, insidious force. Kasparov wrote that Fischer "became the detonator of an avalanche of new chess ideas, a revolutionary whose revolution is still in progress". In January 2009, reigning World Champion Viswanathan Anand described him as "the greatest chess player who ever lived". Serbian grandmaster Ljubomir Ljubojević called Fischer, "A man without frontiers. He didn't divide the East and the West, he brought them together in