Jermaine O'Neal says he'll decide on Tuesday whether or not to undergo surgery on his troublesome left knee.

He has missed 21 games this season because of the injury.

O'Neal has already met with Celtics team doctor Brian McKeon and will seek a second opinion on Monday, and perhaps even a third via telephone.

He would prefer to play through the injury unless the surgery is going to solve the problem completely.

"Surgery is the worst-case scenario for me," said O'Neal. "If it's going to elevate me and get me out of this mode, then I'm all for it. If you can't guarantee me that it's going to get me out of this mode, then I'm not going to do it."

O'Neal wouldn't reveal what the actual injury is, but he did say that he suffered it this season while trying to cut on the court.

"I felt good coming into the season; I didn't have any issues over the summertime," said O'Neal. "I let go, I trained extremely hard and got into the season and had a situation where I cut, I was almost cutting on the court, and all of a sudden my knee flared up."

Electing to have the surgery would likely put O'Neal on the shelf for a majority of the regular season.