DALLAS -- Kevin Durant felt like he was letting his team down through three quarters.
The three-time scoring champion then went on an offensive frenzy in the fourth before watching his supporting cast finish off the Dallas Mavericks.
Durant scored 19 of his 31 points in the fourth quarter, Russell Westbrook had 35 including the go-ahead jumper with 1 minute left, and the Oklahoma City Thunder beat the Mavericks 107-101 on Sunday night.
Durant was 3 of 9 from the floor and hadn't scored in the second half before hitting seven shots in a row during one stretch of the fourth.
"I was frustrated with myself early on and I wanted to stick with it," Durant said. "My teammates kept coming to me. So I just wanted to come through for them."
Even with Durant going on a scoring binge, the Mavericks managed to tie the game at 101 on Dirk Nowitzki's two free throws with 1:20 left.
With Dallas taking the ball out of Durant's hands, Westbrook connected on a 17-footer to give the Thunder a 103-101 lead. With a chance to tie on the next possession, Durant forced Dallas into a shot-clock violation when he blocked Mike James' desperation jumper.
Durant finished off his brilliant fourth by hitting two free throws with 2.2 seconds left.
"Shots weren't falling for me and I turned the ball over," Durant said. "I just had to stick with it and I think I did a good job of that. My first three quarters were below average."
Nowitzki scored 23 points on 8-of-10 shooting, Vince Carter had 18 points and James added a season-high 14 points for Dallas.
The Mavericks, who have made the postseason 12 years in a row, are fighting to stay within reach of the final playoff spots in the Western Conference.
Dallas will play six of its next seven at home.
"They just made more plays down the stretch," Dallas center Elton Brand said. "We had Durant under control for about 75 percent of the game. He just came up big."
Serge Ibaka had 18 points and 16 rebounds for Oklahoma City, which crept within a game of San Antonio for the best record in the West.
The Thunder beat the Mavericks for the 10th straight time, including a sweep in the first round of the playoffs last year. Oklahoma City won all four matchups this season, three of which were by six points or fewer.
"That's what it seems to come down to every game," Thunder coach Scott Brooks said. "It comes down to the last two or three minutes of the game."
With top defender Shawn Marion missing his sixth straight game with a strained left calf, Carter and rookie Jae Crowder took turns guarding Durant in the fourth, and neither had much luck slowing down the four-time All-Star.
Darren Collison hit a bank shot to finish a 7-0 run and put the Mavericks up 79-78 with 9:43 remaining.
That's when Durant began to take charge. The lanky forward hit a 21-footer and then drove past Carter for a three-point play, giving the Thunder an 83-79 lead.
That started a run for Durant where he scored 17 of his team's next 21 points. He capped his scoring frenzy with a step-back jumper that pushed Oklahoma City's lead to 99-93.
The Mavericks went on an 8-2 run to tie the score. Nowitzki hit four free throws in a row to tie it at 101.
After Westbrook's jumper made it 103-101, Dallas had a chance to tie. But they nearly lost control of the ball twice and James was forced to fire up a tough shot, which was easily blocked by Durant.
With the shot clock winding down, Sefolosha turned over Mayo and hit a 13-footer with 12.5 seconds left, giving Oklahoma City a 105-101 advantage. Durant made two free throws to finish the scoring.
Nowitzki hit his first eight shots and scored all of Dallas' points in an 8-2 run that gave the Mavericks a 59-56 lead early in the third.
Nowitzki finally missed five minutes into the third with an errant 3-pointer.
Westbrook finished the third with a jumper that gave the Thunder a 73-72 lead.
Derek Fisher who played nine games with the Mavericks earlier in the season, played for the first time in Dallas since the team granted his release. Fisher said he was having a difficult time being away from his family and Dallas waived him on Dec. 22.
Fisher ended up signing with Oklahoma City last month and Mavericks owner Mark Cuban said before the game he was disappointed with how the situation with Fisher played out.
Dallas fans booed Fisher when he entered the game with 1:45 left. They then cheered loudly 10 seconds later when the 17-year veteran was called for his first foul.
Brand replaced Chris Kaman in the starting lineup for the Mavericks, who have used 21 different starting units this season. ... Oklahoma City C Hasheem Thabeet was out with a sore lower back.