Charissis originally suffered the injury in a loss at Arizona on January 17 and aggravated the ankle injury in pregame warmups before Saturday's rematch with the Wildcats. Charissis, a 6-11 junior, went up for a rebound and came down awkwardly on a basketball.

Charissis had started 18 straight games for the Trojans, despite averaging only 2.3 points and 10.4 minutes. USC is hoping to have the native of Athens, Greece back for postseason play.