(REUTERS) - Marcus Morris made a go-ahead 3-pointer with 1.2 seconds remaining as the Boston Celtics snapped the Oklahoma City Thunder's six-game winning streak, 100-99, Tuesday night in Boston.
Russell Westbrook missed a 3-pointer at the buzzer that would have given Oklahoma City its seventh straight victory, one shy of its season-high.
Jayson Tatum scored a team-high 23 points and grabbed 11 rebounds and Morris added 21 as the Celtics bounced back from Sunday's 108-89 loss in New Orleans to win for the fourth time in eight March games.
It was Tatum's first-career game with at least 20 points and 10 rebounds. Westbrook had 27 points, eight rebounds and nine assists to lead Oklahoma City. Paul George added 24 points and 13 rebounds, Steven Adams had 14 points and seven boards and Carmelo Anthony scored 13 for the Thunder.
Greg Monroe contributed 17 points and six rebounds, Terry Rozier added 14 points and Shane Larkin added 13 for the Celtics, who had lost three of their last four coming in and were shorthanded on Tuesday.
Kyrie Irving missed his fourth consecutive game for the Celtics with soreness in his left knee, and is set to receive receive a second opinion on his knee.
Boston's Jaylen Brown (concussion) sat out for the fifth straight game while Marcus Smart (right thumb sprain) missed his fourth in a row. Shane Larkin's 3-pointer to beat the third-quarter buzzer brought the Celtics within 75-73 entering the fourth.
Westbrook hit a pair of free throws with 24.7 seconds remaining to put Oklahoma City up 98-92.
Tatum answered with a finger roll layup with 17.6 ticks left before Westbrook made one of 2 at the foul line with 16.8 left to make it 99-94.
Rozier hit a 3 with 12.7 seconds to go and Anthony missed both of his free throws with 8.4 seconds left, setting up Morris' heroics after a Celtics'timeout.
The Thunder were up 48-45 at halftime after leading by as many as 10 in the first half.
Before the game, the NBA announced it had fined Boston forward Morris US$15,000 for his verbal abuse of a game official following Sunday's loss to the Pelicans. Oklahoma City hosts Miami on Friday.
Boston opens a four-game road trip Friday in Portland.