Word that 10-time All-Star Allen Iverson would be returning to Philly wasn't enough to keep the Sixers from suffering their longest losing streak since 2006.
Oklahoma City opened the second half on a 14-5 run to take a 68-61 lead on Thabo Sefolosha's 3-pointer from the left corner, and the Thunder led the rest of the way.
Jeff Green added 19 points, Sefolosha and Nenad Krstic scored 12 apiece and Russell Westbrook had a career-high 15 assists for Oklahoma City.
Andre Iguodala led Philadelphia with 28 points. Thaddeus Young scored 16 of his 20 in the first half, Jrue Holiday added 15 points and Willie Green had 14. Elton Brand scored 13 points in his second game back after missing three games with a sore right hamstring.
Collison, who had missed four games because of a sore right knee, helped put the game away with a right-handed hook shot and a tip-in in a string of six straight points for the Thunder that pushed the lead to 15 at 115-100.
He was pushed into extra action after starting center Nenad Krstic sprained his left ankle in the final minute of the third quarter and did not return. Krstic had missed Oklahoma City's last game with a sore Achilles' tendon in the same foot.
Philadelphia had been within 96-91 after Jason Kapono's 3-pointer with 7:57 to play, but Mike Wilks answered at the other end and the Thunder kept pulling away.
The 76ers announced earlier in the day that Iverson would be ending a brief retirement to return to the team he led to the NBA finals eight years earlier. Iverson isn't expected to join the Sixers until Monday, when they begin a five-game homestand, their longest of the season.
On Saturday, they'll complete a stretch playing seven out of eight games on the road. They're 0-7 so far. The last time the Sixers had lost more than seven games in a row was a 12-game skid in November and December 2006.
Durant's scoring total left him seven points short of 4,000 in his career. He would be the second-youngest player to reach that mark, behind only LeBron James.
NOTES: Oklahoma City is 8-0 when scoring at least 100 points. ... The teams combined to hit their first eight 3-pointers, five by Philadelphia and three by Oklahoma City. ... Former Dallas Cowboys defensive lineman Leon Lett was in attendance.