The Celtics guard clearly was irked by Giannis Antetokounmpo and the Bucks benefitting from some questionable calls, including an overturned foul call that would have caused Antetokounmpo to foul out late in the fourth quarter.
The first incident came with 2:30 remaining. Antetokounmpo appeared to foul C's big man Daniel Theis, but a review ruled it wasn't a "hostile act."
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Then, with the game tied at 107, Antetokounmpo was called for an offensive foul while driving on Smart, who got his feet out of the restricted area and looked to have taken a charge. Rather than it being Antetokounmpo's sixth foul, the call was overturned and Smart was hit with a blocking foul.
Antetokounmpo's basket counted, and he hit the free throw to give the Bucks a 110-107 lead and all of the momentum in the final minute.
Watch the controversial play below:
Smart called out the referees after the game when asked about the play.
"The excuse was I was late on the charge. The replay center said I was late and it was a block," Smart said. "Quite frankly, I think we all know what that was about. Giannis has 6 fouls. They didn't want to get him out. Let's just call a spade a spade. That's just what it is."
Yeah, it's safe to say he wasn't thrilled.
Smart's frustration is understandable. Especially after a game in which he contributed 23 points off the bench and was the primary reason the Celtics were able to keep up with the Bucks after a slow start.
Nonetheless, the C's simply have to eat the tough loss and move on to their next matchup inside the Orlando bubble.