Oklahoma City, OK (SportsNetwork.com) - Russell Westbrook scored 36 points and led a third-quarter barrage that lifted the Oklahoma City Thunder to a 122-118 victory over the Boston Celtics.

Westbrook recorded 15 points during a third quarter in which Oklahoma City outscored Boston by a 40-24 margin, then put up 10 more in the fourth to help the injury-plagued Thunder to an important win.

"He changed the game around with his defense and his passing," Thunder head coach Scott Brooks said. "That's what special players do. Every night, you're not going to make shots. You have to be able to pass and defend. He did a great job tonight."

Wednesday's result moved Oklahoma City, still without Kevin Durant and now minus Serge Ibaka for likely the remainder of the regular season, a half-game in front of New Orleans for the Western Conference's eighth seed.

Enes Kanter finished with 22 points and 10 rebounds starting in Ibaka's place, while Anthony Morrow gave Oklahoma City a huge lift off the bench by pouring in 20 points on 7-of-11 shooting. Westbrook added 10 assists.

The Celtics, locked in a battle with Indiana and Miami for the East's final two playoff spots after winning a season-high five straight coming in, received a career-high 25 points and nine rebounds from Marcus Smart. Kelly Olynyk and Brandon Bass each tallied 20 points in defeat.

Down 68-62 nearing the midway mark of the third quarter, the Thunder surged ahead behind a 17-2 run and remained in front the rest of the way. Westbrook netted eight points during the tear, which Morrow capped with a 3-pointer to stake Oklahoma City to a 79-70 advantage.

"In the second quarter they got after us, then we changed our whole mindset," Brooks remarked. "We were going to be aggressive, fight through screens and use our bodies to bump, and then we did."

The Celtics later cut the lead down to four, but the Thunder responded with a 13-1 flurry that overlapped into the opening two minutes of the fourth quarter. Oklahoma City forced three turnovers and went 7-of-7 from the foul line during the sequence, which had the home team up by a 97-81 count.

"We didn't balance poise and assertiveness in what we do well," said Celtics head coach Brad Stevens. "It's a fine line. Credit (Oklahoma City)."

Boston did battle back and managed to pull within 108-103 after a 12-3 stretch that ended in back-to-back treys from Smart and Olynyk, the last coming with 2:30 left. The Celtics managed just two free throws on their next four possessions, however, and Oklahoma City stretched the lead to 11 before holding on in the closing moments.

The Thunder owned a 28-24 edge after one quarter behind Kanter's eight points and five rebounds, and were up by seven nearly four minutes into the second before Boston put together the game's first big run. Olynyk recorded the first five points of a 14-4 spurt which ended in a Smart triple that gave the Celtics a 43-40 lead with 4:14 to go in the half.

Another trey from Smart had Boston ahead by seven late in the second quarter, but a Morrow 3-pointer and Westbrook's layup around a Bradley dunk pulled Oklahoma City within 57-53 at the break.

Game Notes

The Thunder have now won 11 straight at home against Eastern Conference teams ... Ibaka underwent arthroscopic knee surgery on Tuesday and is expected to be sidelined from 4-to-6 weeks, while Durant remains sidelined by a foot injury ... Smart went 7-of-12 from 3-point range and the Celtics were 13-of-34 overall from beyond the arc ... Steven Adams posted 14 points and 13 rebounds for Oklahoma City ... Boston scored 26 points on 20 Thunder turnovers, including seven from Westbrook ... The Thunder ended 33-of-39 from the foul line.