CHICAGO — DeMar DeRozan scored 28 points, Zach LaVine added 22 and the Chicago Bulls stopped Boston’s nine-game win streak, beating the Celtics 121-107 on Monday night.

Patrick Williams scored a season-high 17, and the Bulls made it look rather easy against the team with the NBA’s best record. They led by 13 at halftime, got it up to 21 in the third quarter and withstood a push to come away with the win after dropping four straight and 5 of 6.

DeRozan, who scored 41 in Friday’s loss to Orlando, scored eight in a span of just over a minute late in the third. He also spun and fed Alex Caruso for a reverse layup that made it 116-101 with just under three minutes left in the game.

LaVine bounced back after scoring four against the Magic and getting benched in the closing minutes. He had nine points in the fourth quarter.

Jayson Tatum led Boston with 28 points. Jaylen Brown scored 25, and Malcolm Brogdon finished with 23 points, nailing 5 of 6 3-pointers.

The Bulls led 46-31 in the second quarter after Coby White hit a 3 to cap a 15-2 run and were up 63-50 at halftime.

LaVine hit a 3 early in the third to make it 74-53. It was a 19-point game before Brogdon made a 3 in the closing seconds to start an 11-0 run.

NOTES: G Marcus Smart (right ankle inflammation) was available after missing the previous two games. Interim coach Joe Mazzulla said the Celtics will manage if Smart — the reigning Defensive Player of the Year — has to sit out games every now and then. “I trust his work ethic, his ability to stay healthy,” he said. “If it swells up, then he’ll do what’s best for the team. I trust that.” … The Celtics attempted 22 shots in the first quarter and 17 were 3-pointers. They made five from beyond the arc and six field goals in all in the period as Chicago grabbed a 28-23 lead.