Celtics center Jermaine O'Neal was ruled out for the second half of the team's loss to the Mavericks on Monday night because of a sore left knee.

O'Neal started and played 11 minutes in the first half.

He said after the game that he had "no explosion" and decided that the Celtics would be better off with him on the bench.

The knee first became sore after Boston's loss to Cleveland on the second night of the regular season.