Jermaine O'Neal weighs surgery options

WALTHAM, Mass. -- Boston Celtics coach Doc Rivers said that center Jermaine O'Neal underwent an MRI on Wednesday on his ailing left knee and, while he hadn't seen the results yet, he indicated that in-season surgery is a likely possibility as Boston looks to cure what's nagged at O'Neal his first three months with the team.

O'Neal sat out Wednesday's game against the Sacramento Kings, the 21st game he's missed this season because of lingering soreness in a knee that's bothered him throughout the latter stages of his career. O'Neal met with the team brass Thursday morning to discuss options and admitted surgery is inevitable -- it simply comes down to whether it will come during the season or after.

"[In-season surgery] was definitely something we talked about the first time I was out for the extended period of time," O'Neal told Boston sports radio WEEI (850 AM) on Thursday during a weekly Celtics call-in segment. "We wanted to try a couple of other options. We may be looking at that situation now. [Surgery] is something that I will eventually need, at some point -- at the end of the season or if it's in-season -- but you want to be around. You don't want to miss extended periods of time ... I already did that. So you make your decisions as a player and you listen to the staff, and, if they have a certain way, then you try that out and if it doesn't work you have to go with the next-best scenario.

"I'm going to run in to see the doctor again in just a second with the team trainers and [Celtics president of basketball operations] Danny [Ainge] and those guys and we're going to make a decision on ultimately what's best for me to get better and be done with the ailment and be back on the court full time."

Rivers hinted that in-season surgery was the likely option after a two-month rest didn't work. After missing 20 games due to the knee, O'Neal returned for 10 games starting on Christmas, but sat out the second half of Friday's win over the Toronto Raptors while admitting to soreness from the renewed activity.

The knee swelled up Wednesday morning, forcing him back to the bench before Boston's lopsided win over the Kings.

"My guess is he's going to have to do something; I don't know that, but I'm using my doctorate," joked Rivers, who has always been fond of noting that 'Doc' is merely his nickname. "My guess is that he'll probably have to do something."

And what happens if O'Neal does need in-season surgery?

"It puts more pressure on all of us," said Rivers, before revealing that reserve center Semih Erden, who filled in nicely for O'Neal on Wednesday, posting career highs with 10 points and eight rebounds, missed Thursday's practice due to an aggravated groin pull.

Shrugged Rivers: "Hey, it's who we are."

Chris Forsberg is the Celtics reporter for ESPNBoston.com. Follow him on Twitter.