A weekend motorcycle crash in Marietta left a champion boxer paralyzed.

Two-time World Boxing Organization welterweight champion Paul Williams was severely injured Sunday morning when he wrecked his motorcycle on South Marietta Parkway.

Williams, 30, was thrown from the bike, and his spinal cord was severed. The boxer is a native of the Augusta area.

Marietta police spokesman David Baldwin said Williams was traveling east on South Marietta Parkway near Atlanta Road "at a high rate of speed" shortly after 7:30 a.m. Sunday.

"The motorcycle, which was traveling too fast for conditions, could not negotiate a curve and left the roadway," Baldwin said. "The motorcycle crashed into an embankment and Williams suffered serious injuries."

"From the waist down, he has absolutely no movement. He's in very good spirits, though," his manager, George Peterson, told The Associated Press from his home in Aiken, S.C. "He still believes he's going to fight again."

Williams was in the area to attend his brother's wedding Sunday afternoon, Peterson said.

"I know he's going to make a statement after surgery on Wednesday, because he's that kind of person," Peterson said. "He's 100 percent coherent and still has the will to want to get back on the motorcycle."

Williams was scheduled to fight Saul "Canelo" Alvarez on Sept. 15 in Las Vegas but that event has been canceled, Peterson said.

"Right now, there's no thinking about any fights right now except for the fight that's facing Paul right now — to get movement back in his body and keep the movement that's above his waist," his longtime promoter, Dan Goossen, told AP.

Peterson said he continues to hope with Williams that the boxer's career isn't over.

"I want to think along with him, 'cause I've seen him do things in his boxing career that shouldn't have happened," he said.

Williams is among the most versatile and unusual athletes in boxing, making him a highly undesirable opponent for the world's best fighters during his lengthy, successful career. He has competed effectively in an impressive three weight classes against much shorter foes, even comfortably making the 147-pound welterweight limit despite his lanky 6-foot-2 frame.

Williams won his first major welterweight title in July 2007 with a decision over Antonio Margarito. He struggled to land fights with the sport's biggest stars because of his pronounced size advantages, a high-volume punching rate and his relative anonymity, but was considered one of the world's top pound-for-pound stars.

He earned victories over Carlos Quintana, Winky Wright, Sergio Martinez and Kermit Cintron, but Martinez abruptly stopped Williams' rise in November 2010 with a second-round victory in their rematch. Williams ended up face-down on the canvas with his eyes wide open in perhaps the most spectacular knockout in recent boxing history.

Williams was unimpressive in his next two fights, but his bout with Alvarez — the popular young Mexican star — at Las Vegas' MGM Grand Garden was his return to the big time — and a chance to win Alvarez's WBC 154-pound belt.

"We want his fans to know he's going to be all right and he'll be back," Peterson said. "He said if he wasn't going to be boxing, he's going to be a stand-up comedian."

The Associated Press contributed to this article.