The Celtics, who survived a Game 7 showdown in each of the first two rounds of the playoffs, lost a post-season game at home for the first time this year. They have yet to win on the road in the playoffs and head for Detroit Saturday for Game 3.

Detroit led by as many as 11 points early in the fourth period, but Paul Pierce brought Boston within four when he made a layup with 40 seconds remaining.

Billups then gave the Pistons a 100-94 advantage by making a reverse layup coming out of a time out. Ray Allen's three-pointer with 10 seconds left gave Boston some hope, but Detroit's Rasheed Wallace made one of two free throws to boost the lead back to four.

A three-point attempt by Kevin Garnett failed to go with three seconds remaining and Tayshaun Prince added two free throws for the final margin.

Richard Hamilton led Detroit with 25 points and Billups had 19.

Pierce had 26 for the Celtics, Allen contributed 25 and Garnett scored 24.