ORLANDO, Florida — Cleveland Cavaliers guard Kyrie Irving sat out Friday night’s game against the Orlando Magic because of a left knee contusion.

The fourth-year veteran said he felt his knee “buckle” against the Oklahoma City Thunder on Dec. 11 after making contact with Russell Westbrook, but was able to re-enter the game after briefly heading to the locker room for treatment. He re-aggravated the injury late in the fourth quarter of the Cavs’ 101-91 loss to the Miami Heat on Thursday, when he hyperextended his left knee while trying to make a play in the paint.

The Cavs said an MRI was unnecessary for Irving’s knee after the Heat game, however.

Irving warmed up on the court at Amway Center with trainer Stephen Spiro prior to the Cavs’ game against the Magic and determined he was unable to go.

He approached LeBron James in the locker room pregame to inform James of his status and said, “Do your thing tonight.”

The former No. 1 pick had been on an uptick of late, averaging 27 points on 57.9 percent shooting in his last two games. He averages 20.3 points, 5.3 assists, 2.9 rebounds and 1.5 steals while shooting a career-high 47.0 percent to go with a career-low 1.9 turnovers per game.

Cleveland started backup point guard Matthew Dellavedova in Irving’s place.

Also Friday, Cavaliers center Anderson Varejao had surgery to repair his torn left Achilles tendon at the Cleveland Clinic. He will miss the remainder of the season.