Boston Celtics forward Leon Powe underwent successful left knee surgery on Tuesday but his exact timetable for return to NBA playoffs is uncertain.

Powe tore his anterior cruciate ligament and meniscus on April 20 in the first quarter of Boston's 118-115 victory over Chicago in game two of their opening-round series, a playoff matchup the Celtics won in seven games.

Powe, in his second NBA season, averaged 7.7 points and 4.9 rebounds a game this season for Boston.

The defending NBA champion Celtics lost 95-90 to Orlando on Monday in the opening game of their second-round series.

The Celtics and Orlando continue their second-round series on Wednesday.

(Xinhua News Agency May 6, 2009)