Celtics president of basketball operations Danny Ainge confirmed Thursday during his weekly appearance on Boston sports radio WEEI that the team is "monitoring" former Portland Trail Blazers center Greg Oden, but haven't made an attempt to sign the 7-footer.

A report from CBS Sports on Thursday listed the Celtics as one of several teams interested in Oden, a 24-year-old who's already undergone three microfracture surgeries during his NBA career.

"Yeah, so we're monitoring Greg, like all the NBA teams are, but we have not attempted to sign him," Ainge said Thursday. "But we are monitoring him and having (conversations) with his people just to see where he's at."

Oden hasn't played in an NBA game since December 2009, and reportedly wouldn't return until the 2013-14 season.

"I don't think (he'd be ready to play this year)," Ainge said. "I don't know any of that for sure, but I would suspect that anybody that would sign him would have their eyes looking more towards his contribution in the future than now."

Ainge said that in the brief time Oden did play in the NBA -- a total of 82 games -- he showed flashes of the talent that made him the No. 1 overall pick in the 2007 draft.

"I think that there's been stretches, very few stretches, where he's played excellent ball," Ainge said. "He's been a terrific defender and a fantastic offensive rebounder and just a real big, strong presence on the inside. I think that he's been that."

Despite Oden's significant injury history, Ainge said he expects there to be competition for his services.