Sustaining his fourth concussion in four years with Charlotte, Wallace was taken to a hospital. A team official said Wallace was suffering some amnesia, but tests showed no fractures and no internal bleeding.
Wallace was released from the hospital later Friday, but did not accompany the team to Washington for Saturday's game against the Wizards. It was uncertain when Wallace would be cleared to play again.
"That's my teammate, so I'm upset," Bobcats guard Raymond Felton said after the Bobcats' 116-115 overtime loss. "He was knocked out. He was knocked out cold."
Wallace was double-teaming Kings forward Mikki Moore in the post early in the third quarter and was called for a foul a moment before Moore swung around with the ball. Moore's right elbow hit Wallace directly in the nose.
Wallace crumpled backward to the floor, before turning onto his stomach. He then lost consciousness and remained on the floor for almost 10 minutes while the training staff and team doctor attended to him. Wallace was eventually strapped to a stretcher with a neck brace and wheeled off the floor to an ambulance in the loading dock area of the arena.
Moore said he didn't see Wallace on the play.
"They said I gave him a concussion," Moore said. "I'm going to pray on it all night."
Moore appeared visibly upset during the long delay and Kings coach Reggie Theus came on the court to talk to Bobcats coach Sam Vincent while Wallace was being attended to.
Wallace, who came in averaging 20.9 points per game, had six points and six rebounds in 21 minutes.
"It was disturbing to see him go out on a stretcher because you expect him to get back up after hits like that," Bobcats guard Jason Richardson said. "It was a little scary."