The Dallas Mavericks lost All-Star Kyrie Irving to a scary knee injury on Monday night in their matchup against the Sacramento Kings. The former Celtics guard felt awkwardly to the ground while attempting a layup with 2:35 remaining in the first quarter. Irving stayed on the ground for a long stretch while being attended to by Mavericks trainers. He eventually was helped to the free throw line where he made both free throws before being helped off the floor by Dallas staffers.

The Mavericks announced that Irving has been diagnosed with a sprained knee and was ruled out for the remainder of the game. He finished with seven points in nine minutes before suffering the injury.

The Mavericks are already playing without All-Star trade addition Anthony Davis who suffered an adductor strain during his first game after being acquired from the Lakers. Dallas also is without Dereck Lively (ankle), Daniel Gafford (knee), Caleb Martin (hip) and PJ Washington (ankle) for Monday’s game. Lively, Gafford and Martin have all been long-term absences and Irving’s injury will be a further test to the Mavericks’ depth as they battle for playoff positioning in the Western Conference.

The Mavericks entered Monday’s action at 32-29, holding the 10th spot in the Western Conference. They do hold a comfortable four game lead over the Phoenix Suns for the play-in tournament but all their top three bigs are expected out for several more weeks. A long-term injury to Irving could leave Dallas with very little margin of error moving forward.

Irving is averaging 25.0 points and 4.7 assists per game in 50 appearances this season.

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