Jermaine O'Neal's tenure with the Celtics isn't starting off quite as the veteran planned.

O'Neal sat out practice for the second straight day on Monday because of a tight left hamstring.

Boston coach Doc Rivers said O'Neal will be sidelined for the remainder of the week as a precautionary measure.

"I just think that, when you look at [Shaquille O'Neal] and Jermaine, and think they can play 82 healthy games -- that'd be nice, but we have to be ready for them to miss a couple games and be able to play through it," Rivers said. "That's why guys like Luke [Harangody] and Semih [Erden] are so important. Until [Kendrick Perkins] comes back, they're going to have to play, one of them at least.

"The first 10 games, we don't have D-West [due to suspension]. So someone else might have to play, or we go with a shorter rotation to start the season by playing Paul [Pierce] and Ray [Allen] more minutes, just until D-West comes back. That's up to how our other guys work out and how well they play."