< Jaylen Brown

scores 19 points as the Celtics hand the Pistons their first loss with a 109-89 win Detroit.

Detroit — With Jaylen Brown struggling offensive so far this season, Brad Stevens still asked him if he wanted a shot at defending one of the NBA's hottest players.

Not only did Brown slow down the much bigger Blake Griffin, his offense also perked up in the process.

Brown scored 19 points and Marcus Morris added 18 for the Boston Celtics in a 10989 victory on Saturday night over the Detroit Pistons, who lost their first game of the season.

Brown came in averaging 8.6 points per game this season, down from 14.5 last year.

“I wasn't tripping,” Brown said. “And I've guarded bigs before, especially my rookie year. Actually when Blake was (with the Los Angeles Clippers), I guarded him a little bit. So I was familiar when Brad asked me.”

Andre Drummond had 18 points and eight rebounds, and Stanley Johnson scored a season-high 16 for Detroit, which had won its first four games of the season for the first time since 2008-09.? Griffin came in averaging 33.8 points per game, shooting 55.7 percent from the field and 65.2 percent from 3. He missed his first seven shots.

Griffin scored seven points in 30 minutes, finished 2 of 13 from the field and 0-4 from deep.

“Blake's a handful,” Stevens said. “We knew we were mostly going to have to play small on (Griffin) or Drummond, so we just tried to be very active around those guys.”

Detroit came in shooting 37.6 percent from 3-point range this season, and went 7 for 37 (18.9 percent). Boston shot 14 for 34 (41.2 percent) from deep.

The Celtics opened up a 103-74 lead with 5:15 left to play, cruising in the first of consecutive games.

Pistons coach Dwane Casey was assessed his first technical foul with Detroit, protesting a first-quarter no-call after Griffin hit the ground. The subsequent Morris free throw capped an 8-0 run that made it 23-11 Boston in the first quarter.

The Boston bench outscored Detroit's 34-9 in the first half, as the Celtics opened up a pair of 26-point leads in the second quarter.