New York Knicks forward Quincy Acy was ejected after he threw a punch at the Washington Wizards' John Wall during their Christmas Day clash.
Wall handled the ball in transition when Acy approached and levied a hard foul in the fourth quarter of the Knicks' 102-91 loss at Madison Square Garden.
Wall took exception and responded with a push to Acy's chest, for which he received a technical foul.
Acy answered with a wild right-hand swing at Wall, with his fist not connecting.
The 24-year-old claimed he did nothing wrong.
"I didn't throw a punch. I got up and reacted, then I just grabbed him," Acy said.
He added: "It was just a foul. If somebody has a fast break and you step up and grab them, it's the same concept."
Wall said he was frustrated with the contact, despite bracing himself for a physical foul.
"I was just dribbling the ball up, and then I just got pushed with two elbows, and I got up and gave him a shove back, and then after that the refs and teammates broke it up, and that was the end of it for me," Wall said.
"I was just running down the court. Usually I think I just get a regular foul but I could tell like how he charged [it was going to be a physical foul].
"When I fell, I kind of was frustrated, but I didn't try to retaliate in the wrong way to get ejected or anything."
Wizards players were on hand to break the two players apart before any further damage was done.
Knicks star Carmelo Anthony grabbed Acy away from the fray, and team personnel later walked him to the locker room.
The Knicks have endured a frustrating season, as their Christmas defeat was their sixth loss in succession as they slumped to a 5-26 record.