Kevin Garnett led the way for Boston with 18 points and 10 rebounds, but every starting Celtic scored in double figures. Paul Pierce had 18 of his own, while Jason Terry and Rajon Rondo added 17 apiece.
Kevin Love paced the Timberwolves in scoring with 19 points. He also grabbed a game-high 13 rebounds, but the Celtics won the battle of the boards, 45-41.
Boston went into the break down by four but used a 9-0 third-quarter run to seize control and go up 67-61. That spurt was capped by a three from Terry, who made three of his five attempts from long distance.
The Celtics eventually extended their lead to 17 as they coasted to the home victory in the fourth quarter.