Facing a tough crowd after rejecting the Lakers last summer, the five-time NBA All-Star scored nine of his points in the fourth quarter as the Thunder fought their way back from a five-point deficit.
The victory puts Oklahoma on seven wins from 10 games, while the Lakers have fallen to 1-3 since losing LeBron James to a groin injury.
Ben Simmons scored 29 points and JJ Redick added 27 for the 76ers who narrowly saw off a second-half rally from the Suns after leading by 30 in the third quarter.
The Detroit Pistons ended a three-game losing run, beating the Memphis Grizzlies 101-94.
Blake Griffin was among six Detroit to reach double figures, scoring 26 points, while the Grizzles extended their losing streak to three games.
Chicago chased the Orlando Magic all night as the Bulls struggled to put up a defence to 22 points from Nikola Vucevic and 18 from Aaron Gordon at the United Center.
Leading 62-45 at halftime, Orlando stretched the lead with 11 straight points at the start of the third, and continued to dominate from there to see out the 112-84 win.
Elsewhere, the Brooklyn Nets beat the New Orleans Pelicans 126-121 after taking a 73-point advantage at half-time, while Washington Wizards defeated the Atlanta Hawks 114-98 thanks to 24 points from Bradley Beal and the Miami Heat toppled the Cleveland Cavaliers 117-92.
Gordon Hayward scored a season-high 35 points in the Boston Celtics' 115-102 win over the Minnesota Timberwolves, the Washington Wizards downed the Atlanta Hawks 114-98, and the Dallas Mavericks emerged 122-84 winners over the Charlotte Hornets.