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 yet when it was thrown at Fischer suddenly, he faced its consequences alone and won by applying simple, classic principles. Upon completion of the match, Petrosian remarked: "After the sixth game Fischer really did become a genius. I on the other hand, either had a breakdown or was tired, or something else happened, but the last three games were no longer chess." "Some experts kept insisting that Petrosian was off form, and that he should have had a plus score at the end of the sixth game..." to which Fischer replied, "People have been playing against me below strength for