Years followed when he made no visible progress, and others had the chance to challenge for the world title. Vasily Smyslov and Mikhail Tal both won the world title, yet lost it back to Botvinnik in return matches. At last, in 1962, Tigran won the Candidates tournament, and became the new challenger to Botvinnik. Petrosian also won the very strong Soviet Championship four times, in 1959 (Tbilisi), 1961 (Moscow), 1969 (Moscow), and 1975 (Yerevan).