OKLAHOMA CITY – It has happened quietly and without much fanfare, but the Oklahoma City Thunder are on a roll. After starting the season at 8-12, the Thunder had won 10 of their last 13 games heading into their Christmas matchup with the Houston Rockets Monday night.

While Oklahoma City’s offense, which had been below average, has shown improvement, the foundation for their recent run has been the overall team defense. That is an element very few people expected from a group of All-Stars who were put together in the offseason.

But it was that defense that showed up down the stretch Christmas night that sealed a 112-107 victory against the high scoring Rockets.

“I thought we took on the challenge; we knew it was going to be tough,” Thunder forward Paul George said. “We knew we were going to be tested with their ability to spread out and shoot, but again I thought we just did a great job taking on that challenge.”

No sequence better exemplified the Thunder defensive tenacity than when Andre Roberson was guarding Houston’s James Harden with 30 on the clock and Oklahoma City leading by three.

Throughout the night Harden had been able to use his quick release to hoist up a 3-pointer despite tight defense coverage. So with the game on the line, he tried the same shot from the top of the key.

However, Roberson was ready for it. He timed Harden’s release and blocked the 3-point attempt. Russell Westbrook got the ball then fed Roberson for a layup to put Oklahoma City up 112-107 and essentially put the contest away.

“Yeah, he has obviously played against him a lot,” Thunder coach Billy Donovan said of Roberson defending Harden. “And I have said this before, not only does Andre have great defensive ability, but he is really smart and he is experienced and he has played against the elite players in this league. Harden is a really, really hard guy to defend.”

Harden ended the night with 29 points on 7 of 18 shooting, to go along with 14 assists. Trevor Ariza and Eric Gordon each posted 20 points in the loss.

Westbrook led all scorers with 31 points as he made 12 of his 24 shots. He also collected 11 assists and six rebounds.

George scored 24 points and Carmelo Anthony added 20. Steven Adams posted 15 points and 10 boards. With 6 points and four steals, Roberson was the only Oklahoma City starter not to score in double figures, but his teammates felt his impact regardless.

“He lifts our team to another level when he is playing that well defensively,” Anthony said. “It puts a challenge on us to have his back, to be there for him, to step it up another notch on the defensive end. When he plays like that defensively, he gives our team a whole different dynamic.”

Oklahoma City (19-15) now has wins against Golden State, Houston and San Antonio. All three victories came at home, where they hold a 13-4 mark.

The Thunder carries their five-game winning streak into a Wednesday night matchup with Toronto (23-8), where they will find another streaking team. The Raptors are 9-1 in their last 10 games and have the best record in the Eastern Conference.

It’s another chance for the Thunder to showcase their defense against stiff competition.

“I still think for us there is still a lot of room for improvement and areas that we can get better,” Donovan said, “but I think that we continue to improve and get better.”