OKLAHOMA CITY -- As Oklahoma City grinds its way through a grueling month of basketball, any win is normally a reason to be happy.

However, there were no smiling faces in the Thunder locker room Thursday after they defeated the Dallas Mavericks 109-98 at Chesapeake Energy Arena.

Even though they picked up the victory, it came at a price for Oklahoma City. Enes Kanter fractured his right arm in the game. No timetable has been set for when he will return to action.

Kanter is Oklahoma City's third-leading scorer and third-leading rebounder. He is also a top candidate for the NBA's Sixth Man of the Year Award.

While Kanter's loss will impact the team going forward, the Thunder aren't hanging their heads.

"He's alright, mate," Thunder center Steven Adams said. "Still alive."

Russell Westbrook led all scorers with 45 points. He shot 16 of 29 from the field to go with eight rebounds and three assists. His triple-double streak ended at three games.

Victor Oladipo scored 17 points while Adams added 15 points and seven rebounds to help the Thunder (28-19).

"We were a little more physical," Westbrook said. "We came out in the second half more aggressive on both sides of the ball."

Harrison Barnes paced Dallas with 31 points on 13-of-26 shooting. Justin Anderson came off the bench to post 17 points for the Mavericks (16-30).

Dallas played without four of their top six players, including Dirk Nowitzki, Deron Williams and Wesley Matthews. Devin Harris liked how his team responded to the adversity.

"I think we are understanding how we need to play to be successful to win," Harris said. "Experience helps. Expectations are growing."

With 4:15 left, Barnes scored to cut the Thunder lead to 96-90. But Westbrook answered with a midrange jumper.

Seth Curry knocked down a jumper and Dallas was back to within six with 2:45 on the clock. But once again Westbrook came to the rescue. On three consecutive possessions, he came up with clutch baskets. That included two long range 3-pointers.

On the third jumper, Westbrook spun around in front of the Dallas bench and yelled that Mavs guard Nicolas Brussino couldn't guard him.

Barnes tried to match Westbrook in the final minutes, but was unable to make enough shots. Westbrook hit one more 3 with 25 seconds left to close out the game. He proceeded to dance up the court as the clock ran down.

"We did a great job the whole night," Anderson said. 'Westbrook got hot there at the end shooting threes. We were coming down answering with twos. That's a tough battle to win. We didn't back down. We put our nose in there and fought."

Dallas coach Rick Carlisle was asked about the Thunder having a 36-13 advantage in terms of free throw attempts.

"Trying to get me a $35,000 fine?," Carlisle said. "I have to look at it. I thought there could have been a few blown our way. I'll look at it and see."

Despite being shorthanded, Dallas took it to Oklahoma City at the start as Barnes led the charge offensively. While he didn't shoot efficiently, he was able to get his shots off and posted seven points in the first quarter as the Mavericks led 26-23.

During the month of January, the Thunder watched as their big men were able to take over games. But in the first half against Dallas, Kanter and Adams were held in check.

That put more pressure on Westbrook to pick up the scoring load. While he was able to score 15 points in the half, the Thunder trailed 55-53 at halftime.

Oklahoma City had to play the second half without Kanter, who fractured his forearm slapping a chair in frustration during a timeout. He had to get X-rays at halftime.

"It's tough man," Westbrook said. "Especially doing it the way he did it. I think it's unfortunate, but he's a strong man and he will be back better."

NOTES: The Dallas Mavericks were without four players when they took on the Oklahoma City Thunder Thursday. That included Dirk Nowitzki, who sat out the game to rest. The Mavs were also without J.J. Barea (left calf strain), Deron Williams (left toe sprain) and Wesley Matthews (right hip strain). None made the trip to Oklahoma City. "It's just been that kind of a year," Dallas coach Rick Carlisle said. "Through it we have to manage the situation. We have to move the franchise forward." ... Oklahoma City G Russell Westbrook was named to the Western Conference All-Star reserves Thursday. But his coach believes he should have been named a starter. "There is no question in my mind he should be starting," Thunder coach Billy Donovan said. "I'm not taking anything away from anybody who is starting. But I think people clearly think, in my opinion, that Russell should be starting."