Michael Spinks has retired from boxing because he says his career has run its course.

Spinks, a 32-year-old former heavyweight and light heavyweight champion, was knocked out in 91 seconds by Mike Tyson June 27 in Atlantic City, N.J. On Wednesday, he and his friend and promoter Butch Lewis choked back tears to announce the end of a 12-year career that began after Spinks won a gold medal as a middleweight in the 1976 Olympics.Spinks retired with a 31-1 record and 21 knockouts. He says he left the decision up to Lewis, but agreed that there is no reason for him to fight on.

"I don't see anything else for me to do (in boxing)," Spinks said at a press conference. "I'm not fighting just to be fighting."

Still, Spinks felt a bit awkward saying goodbye to boxing.

"I never retired from anything but selling newspapers, I guess I've come a long way from that," he said. "Twelve years is quite a while to be getting swung at and have to duck so many punches.

"I always thought when the time came I didn't want to retire, I just wanted to quit and let everyone ask `Where is Michael, what happened to Spinks?'

"Then I wouldn't have to practice a speech.

"I thank all of you who love me and even those who don't, I thank you for disliking me. I'll miss it. I'll even miss conjuring up the fear to get in the ring, I'll probably miss that most of all."

Spinks earned $13.5 million against Tyson and $25 million for his career, according to Lewis. Lewis said Spinks will join him at Butch Lewis Productions, helping represent boxers and other professional athletes.

Spinks said he will be the rare boxer who stays retired.

"I can't convince the public (he won't come back), but they'll be in for a surprise if they expect to see me fight again," he said. "I'll tell them, `don't wait on it."'