(CNN) -- Los Angeles Lakers forward Metta World Peace has been suspended for seven games without pay over an elbow blow he delivered to the head of an opposing player, the National Basketball Association said Tuesday. One-time basketball bad boy Ron Artest, who changed his name to Metta World Peace, was ejected Sunday from a Los Angeles Lakers-Oklahoma City Thunder game for striking James Harden. "The concussion suffered by James Harden demonstrates the danger posed by violent acts of this kind, particularly when they are directed at the head area," said NBA Commissioner David Stern, to announce the suspension. "We remain committed to taking necessary measures to protect the safety of NBA players, including the imposition of appropriate penalties for players with a history of on-court altercations."
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NEW: Metta World Peace apologizes to Oklahoma City Thunder fans
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He is suspended without pay for elbowing Thunder's James Harden
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World Peace could miss at least six playoff games, the NBA says
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Lakers GM: "His most recent lapse ... is not to be condoned or accepted"
After scoring against the Thunder in the second quarter, World Peace was cheering his own shot when he hit the @placeholder guard in the back of the head, knocking him down.