Oklahoma City center Enes Kanter sustained a fractured forearm after punching a chair on the Thunder’s bench on Thursday night, a self-inflicted injury that could sideline him six to eight weeks, league sources told The Vertical.

Kanter, the Thunder’s second-highest-paid player at $17.1 million a season, fired his fist into the empty chair in frustration on his way to the bench during a first-half timeout in Oklahoma City’s 109-98 victory over Dallas.

Kanter, 24, left the court and returned to the locker room to undergo X-rays that revealed the fracture.

For the Thunder, the loss of Kanter is a significant blow to the team’s Western Conference playoff chase. He’s averaged 14.6 points and 6.8 rebounds for the Thunder. Kanter is also the team’s most productive bench player.

The Thunder are 28-19 and holding onto the sixth seed in the Western Conference.

Kanter joined the Thunder in 2014 in a trade from the Utah Jazz. He had been the No. 3 overall pick in the 2011 NBA draft.

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