The injury happened with 4:33 remaining in the third quarter and the Thunder leading 91-66.
Roberson, who was in the right corner, broke to the basket as Russell Westbrook lobbed the ball to him. However, Roberson crumpled to the court after his leg bent in an awkward direction. He appeared to land on either his back or buttocks and then slid off to the side of the court.
As concerned teammates gathered around, Roberson was examined by trainers for several minutes before being put on a stretcher — sitting — and was taken off the court. His leg was placed in an air cast.
If Roberson misses any time, the Thunder will miss his defense. Entering Saturday’s game, he ranked second in defensive real plus-minus among players to average at least 20 minutes per game this season. In addition, according to ESPN Stats & Information, the Thunder are averaging 96.8 points per 100 possessions with Roberson on the court and 107.7 points without him.
He was making his 39th start of the season and is averaging 5.0 points and 4.7 rebounds.