Kyrie Irving scored 40 points, including two three-pointers in the final two minutes of overtime as the Boston Celtics overcame a five-point deficit in the extra session to defeat the visiting Philadelphia 76ers 121-114.
Irving, who added 10 rebounds, sent the game into OT by sinking a difficult jumper late in the fourth quarter.
The guard's performance helped overcome 34 points and 16 rebounds by Philadelphia's Joel Embiid.
Jayson Tatum added 23 points and 10 rebounds for Boston. Marcus Morris also scored 23 while Terry Rozier chipped in with 10 points.
Jimmy Butler added 24 points for Philadelphia, JJ Redick had 17 points, Wilson Chandler 15 points and Ben Simmons 11 points, 14 rebounds and eight assists.
The 76ers overcame an 11-point, third-quarter deficit to take a seven-point lead on a three-pointer by Furkan Korkmaz with 8:13 to play in the fourth quarter.
Rozier's three-ball brought the Celtics to within two with 7:14 remaining before a Tatum trey pointer tied the game at 101 with 5:26 left.
Tatum made one of two free throws with 4:53 to put Boston up by one. Then Philadelphia led by one after Embiid's dunk.
After the teams exchanged one-point leads, Chandler hit a three-pointer with 37.1 seconds to go in regulation, and the 76ers led by two points.
Irving tied the game at 108 on his shot with 20.9 seconds left and Redick missed at the buzzer, forcing overtime.
The 76ers scored the first four points of overtime on Embiid's two free throws and Butler's jumper.
Boston's Marcus Smart was called for a technical foul, and Redick made the free throw to give Philadelphia a five-point lead.
Dunks by Tatum and Gordon Hayward cut the lead to one with 2:51 left in overtime.
After Simmons made one of two free throws, Irving gave Boston a two-point lead with a three-pointer with 2:01 to play. He hit another three with 1:29 left, and Boston led by four before pulling away.
The Celtics won their second in a row following a three-game losing streak. The 76ers had won their previous two games.
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