NBA's Chimezie Metu Suspended One Game For Punching Opponent In Head

Sacramento Kings forward Chimezie Metu was so pissed after being fouled during a summer league game Sunday ... he threw a wild punch that connected with his opponent's forehead.

The fight all went down in Sacramento's game against the Dallas Mavericks in Vegas ... when Eugene Omoruyi collided with Metu while the Kings player was going up for a dunk attempt.

In the broadcast footage from the arena, you can see Metu was so upset after being knocked into ... he cocked back his right hand and violently punched Omoruyi in the face.

Cameras showed the haymaker -- albeit with a lot of Metu's elbow -- landed flush ... but, fortunately for both parties, the two were separated before any more fists could fly.

Metu and Omoruyi were eventually ejected from the tilt ... and you can see in the clip, Omoruyi was actually in a bit of pain after getting hit.

But, Mavs summer league coach Greg St. Jean told reporters after the game he expected Omoruyi to be just fine.

Unclear if either Metu or Omoruyi will be suspended from summer league action going forward.

As for the result of the game, Metu's Kings got the last laugh there ... with Sacramento ending up beating the Mavericks, 86-70.