Oklahoma City can only hope it didn't lose Westbrook along with the game.
Westbrook, who fell and was hit in the face by the knee of onrushing teammate Andre Roberson in the final seconds, had 40 points, 13 rebounds and 11 assists. He became the first player to string together three triple-doubles since LeBron James in 2009.
Westbrook, who had a noticeable imprint on his right cheek, did not speak to reporters following the game and was taken to a Portland-area medical facility for further evaluation. There was no immediate word on his condition.
"I think it was one of those games where we turned back into ourselves and late in the game we found a way to get stops. We made plays, made shots and we stayed the course over kind of a rough game," Lillard said.
The Blazers overcame a 15-point, third-quarter deficit and tied it on a tip shot by Aldridge with 4:33 to go.
Rookie Mitch McGary came off the bench for a season-high 20 points -- 12 in the third quarter alone -- for the Thunder.
Portland took the lead with 3:56 left on Arron Afflalo's 3-pointer. Aldridge and Westbrook traded baskets down the stretch before Aldridge made a free throw to put Portland up 111-110 with 44 seconds to go.
Afflalo's free throws made it 113-110, and Wesley Matthews' attempt to intentionally foul Westbrook was ruled a shooting foul on a 3-pointer. Westbrook missed the first, and Lillard made free throws with 1.4 seconds left for the final margin.
The Blazers, who earlier in the season led the Western Conference, are 9-2 at the Moda Center this season in games in which they've trailed in the third quarter.
Westbrook was hit in the face in the scramble following his free throws.
"The guy has the heart of a champion," coach Scott Brooks said. "He comes out every night. There are no excuses ever. He plays the game with everything he has."
The Thunder were coming off a 117-113 overtime loss the night before in Phoenix, snapping their seven-game winning streak. Westbrook had 39 points, 14 rebounds and 11 assists, and rolled his ankle late in that game.
The Thunder were playing without Kevin Durant and Enes Kanter because of injuries. Brooks wasn't certain how long Kanter will be out, saying he believed the injury occurred in the second half of the loss to the Suns.
Westbrook's facial injury, if serious, would be a devastating blow.
Trailing the Thunder 59-47 at the break, the Blazers opened the second half with a 7-0 run to close within 59-54. Oklahoma City answered with a 10-0 run capped by Serge Ibaka's dunk to go up 69-54 and led 89-78 going into the final quarter.
"We never believe that we're out of it," Aldridge said. "We understand that if we turn up our defense and we play at a different level that we're capable, anything is possible."
Westbrook entered the game averaging 30.4 points, 8.7 rebounds and 10.2 assists in February -- garnering him increasing MVP buzz.
"He's been doing that for years -- but obviously he's taking it to another level in February," said Brooks, who called Westbrook a "walking triple-double."
The Blazers acquired Afflalo at the trade deadline from Denver to do just what he did Friday night. Afflalo finished with 18 points, including 11 in the final quarter. His total was the most by a Blazers reserve this season.
"In games like this, you just play, you just play and let your basketball instincts kick in," he said afterward.
Thunder: Visit the Los Angeles Lakers on Sunday.
Trail Blazers: Visit Sacramento on Sunday.
The Associated Press contributed to this report.
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