After winning World titles in 1977 and 1979, Sergey Kornilayev, who competed in freestyle light-flyweight class his entire career, went to the 1980 Olympics as the favorite for the freestyle light-flyweight title, but a surprising loss by fall to North Korean Jang Se-Hong in a final round left him with a disappointing bronze. Kornilayev missed the 1984 Olympics due to the Soviet boycott and was forced to compete at the Friendship Games, where he lost to another North Korean, Kim Cher-Huan, in the final round and had to settle for silver. In addition to his 1977 and 1979 World titles, Kornilayev won two more World titles in 1981 and 1982 and a European title in 1985, while winning a silver at the 1977 Europeans. Domestically, Kornilayev won five Soviet titles (1977-79, 1981-82). After finishing his sporting career, Kornilayev worked as a wrestling coach. He became honorary president of the wrestling club Vityaz in Moscow and also served as the chairman of the board of trustees of the Moscow Wrestling Federation.