In 1988, Tyson became the lineal champion when he knocked out Michael Spinks after 91 seconds. Tyson successfully defended the world heavyweight championship nine times, including victories over Larry Holmes and Frank Bruno. In 1990, he lost his titles to underdog James "Buster" Douglas, by a knockout in round 10. Attempting to regain the titles, he defeated Donovan Ruddock twice in 1991, but he pulled out of a fight with undisputed heavyweight champion Evander Holyfield due to injury. In 1992, Tyson was convicted of raping Desiree Washington and sentenced to six years in prison but was released after serving three years. After his release, he engaged in a series of comeback fights. In 1996, he won the WBC and WBA titles after defeating Frank Bruno and Bruce Seldon by knockout. With his defeat of Bruno, Tyson joined Floyd Patterson, Muhammad Ali, Tim Witherspoon, Evander Holyfield, and George Foreman as the only men in boxing history to that point to have regained a heavyweight championship after having lost it. After being stripped of the WBC title, Tyson lost his WBA crown to Evander Holyfield in November 1996 by an 11th round TKO. Their 1997 rematch ended when Tyson was disqualified for biting Holyfield's ear.