It's just the preseason and tempers are already flaring high. Boston Celtics guard Marcus Smart admitted to reporters that he did give the nod to Cleveland Cavaliers guard J.R. Smith to meet him in the back.

Smart spoke with reporters who clarified his gesture following their on-court altercation during their preseason exhibition Saturday night.

“I told [Smith] to come back to the back. All that on the court, we can handle that off the court. I ain’t with that. And that’s on my mama, may she rest in peace. Ain’t no punk right here.”

Smith shoved Celtics center Aron Baynes after the two got their arms entangled while boxing out for a rebound under the basket. Then, chaos ensued. That's when Smart came in and took a shot to the back of Smith's head.

The two continued on a barking match with each other while several players from both squads calmed their emotions down in time to avoid any further damage. Smith received a technical foul, and Smart was thrown out of the game.

The entire sequence can be seen below.

The fiery Celtics guard, who still seems to be recovering from the his mother's passing a few weeks ago, also admitted that he was having none of the Smith's actions, and that he would always have his guys' backs, as a true teammate should.

This certainly isn't the first time that the two have gotten into a barking match, as Smart also got up into Smith's grill in last year's post-season following a hard foul by Smith on Celtics center Al Horford.

Smart will likely only receive a fine following his actions, and will not be looking at any further suspensions. He will be gearing up for Boston's season opener against their conference rivals, the  Philadelphia 76ers, on Tuesday, October 16th.