MILWAUKEE -- Down five early in the fourth quarter, it was time for the Oklahoma City Thunder to take pride in their defense.

They did just that.

Kevin Durant scored 30 points and Russell Westbrook had a triple-double to lead the Thunder to a 109-99 victory over the Milwaukee Bucks on Saturday night.

The Thunder used a 19-2 run in the fourth quarter for their fourth win in five games. Instead of their top-scoring offense being the reason for that game-clinching run, it was the defense that got the final charge going.

"I told them we had to take some pride in our defensive possessions," Thunder coach Scott Brooks said. "It was an individual effort by a lot of guys. Serge Ibaka did a phenomenal job protecting the basket and blocking and altering their shots. Russell and Kevin did a good job defending their players."

They did more than just a good job.

Milwaukee held a five-point lead early in the fourth quarter. The Bucks would only manage to score seven points down the stretch and commit six turnovers. In addition, the Bucks' best offensive weapon, Monta Ellis, was held to just nine points.

The Thunder are two games back of the San Antonio Spurs for the top spot in the Western Conference playoff race.

"We just put our defense mentality to be aggressive and try to score off our defense," Ibaka said

Westbrook finished with 23 points, 10 assists and 13 rebounds. Kevin Martin added 17 points.

Durant shot 10 of 19 from the field and 9 of 10 from the free throw line in becoming the seventh player this season to score 30 points against the Bucks.

Durant is on pace to join Larry Bird in 1986-87 as the only players to average more than 28 points while shooting over 50 percent from the field, 90 percent from the line and 40 percent from 3-point range.

Ersan Ilyasova had 29 points and 14 rebounds for Milwaukee. Epke Udoh had his first career double-double with 14 points and 10 rebounds.

Milwaukee has lost five of its last six and missed a chance to gain ground on the idle Boston Celtics in the East. Milwaukee is now three games back of the Celtics for the seventh seed.

The Bucks battled back from a horrible first-half shooting performance to go into the final quarter tied at 83. Milwaukee hit five 3-pointers in the third to battle back from a 10-point, first-half deficit.

Marquis Daniels' jumper with 8:39 left gave the Bucks that five-point lead that would be wiped out by the Thunder's closing run. Durant put the game out of reach with a 3-pointer with 2:47 remaining to put the Thunder up 10. Durant scored 11 points down the stretch.

"They took advantage of a couple miscues on our part," Bucks coach Jim Boylan said. "You can't fault our effort. My guys played hard."

Oklahoma City made 13 of its first 19 shots to go ahead 32-28 at the end of the first quarter. The Bucks kept the game tight in the second quarter until the Thunder went on an 11-2 run to lead by 11 with 3:28 left in the half. The Thunder went into the break with a 56-46 lead, with Durant, Westbrook and Martin combining for 41 points.

"It's just maturity," Westbrook said. "Our team did a great job of playing our game the right way."

Game notes
Oklahoma City is 20-7 against the Eastern Conference. The Thunder went 12-5 in March, while Milwaukee finished with a 7-9 record. ... Larry Sanders picked up his league-leading 14th technical foul in the third quarter. ... Former 90's rap star Vanilla Ice performed at halftime. ... Milwaukee Brewers All-Stars Ryan Braun and Rickie Weeks were attendance.