Allen was injured in the fourth quarter of Memphis' game at Dallas on Wednesday night, leaving with blood dripping from his mouth. It was the fourth time Allen has missed a game this season.
Quincy Pondexter started in Allen's place, the fourth start of the season for the second-year guard.
Allen is averaging 10.5 points, 4.0 rebounds and 1.7 steals. His status is unknown for Memphis' next game, home against Dallas on Saturday night.