Boston Celtics guard J.R. Giddens underwent successful arthroscopic surgery on his left knee Tuesday at the New England Baptist Hospital, according to the team. The surgery was performed by team physician Brian McKeon.

No timetable has been set for Giddens' return, but he indicated Sunday that he is expecting to miss a month.

Giddens, the Celtics' first-round draft choice (30th overall) in 2008, has appeared in 21 games this season. He was injured on assignment with the Maine Red Claws of the NBA Development League when he landed awkwardly while nearly being upended on a dunk attempt against the Utah Flash on Jan. 25.

Giddens, who had tweaked the knee the game before against Bakersfield, underwent tests that revealed a slight tear in the meniscus. Despite the setback, Giddens was trying to stay positive.

"It's a bummer, but you sit back and look for a positive," said Giddens. "I can work on other areas of my body and maybe my legs can be stronger than before."