Westbrook broke a tie with Wilt Chamberlain, who had nine straight triple-doubles in 1968, by finishing with 21 points, 14 rebounds and 11 assists. He clinched the record on an assist to George for a 3-pointer with 3:52 remaining in the fourth quarter. It was his 23rd triple-double of the season and the 127th of his career.
George had 12 rebounds and 10 assists for the third triple-double of his career. Rookie Deonte Burton had a career-high 18 points and Raymond Felton added a season-high 15 for the Thunder.
Damian Lillard scored 31 points and Jake Layman added 17 for Portland.
The Thunder shot 56 percent in the first half to lead 68-49 at the break. George scored 21 points and Felton added 15.
The Trail Blazers started the second half on a 7-0 run to make things interesting, and they trimmed Oklahoma City's lead to 87-82 by the end of the third quarter.
Westbrook had five assists heading into the fourth, and he re-entered the game after a rest with 9:36 remaining. He got his first assist of the quarter with 6:54 left, but was up to his ninth with 4:57 to play.
Trail Blazers: CJ McCollum was called for a technical in the second quarter. ... McCollum shot 4 for 15 and Lillard 1 for 10 in the first half. ... Portland shot 33.3 percent in the first half.
Thunder: Forward Jerami Grant (right ankle sprain) and guard Dennis Schroder (personal reasons) did not play. ... George scored 17 points in the first quarter. ... Burton hit a 3-pointer at the first-quarter buzzer. ... Forward Patrick Patterson got his fourth start of the season in Grant's place.
Portland hosts Golden State on Wednesday.
Oklahoma City plays at New Orleans on Thursday.
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