Dallas Mavericks star Luka Doncic will sit out Sunday night’s game against the Oklahoma City Thunder due to a right knee contusion.

It’s the second game of a back-to-back for the Mavericks.

Doncic has been struggling with the injury since Tuesday’s 120-117 loss to the Golden State Warriors.

Doncic, a first-team All-NBA selection the past five seasons, is off to a slow start by his standards after missing the preseason with a calf contusion. He is averaging 28.2 points, 7.8 rebounds and 7.8 assists per game while shooting 42.5% from the floor and 32.1% from three-point range.

He said he felt “a little less” than 100% after Saturday’s 110-93 win over the visiting San Antonio Spurs, which ended the Mavericks’ four-game losing streak.

“It’s just a matter of time,” Doncic said. ‘There just isn’t much time to rest. But I will definitely get better. I promise.’