Center Timofey Mozgov scored 16 points and grabbed seven rebounds and forward Kevin Love had 13 points and six rebounds while battling foul trouble.
Boston guard Isaiah Thomas, who finished second this week in Sixth Man of the Year balloting, finished with 22 points, including 10-of-10 shooting at the free-throw line on a night the Celtics' bench out-scored the Cavs 51-7.