Boston Celtics fans understandably weren't pleased with Kemba Walker's ejection in the third quarter of Wednesday night's game vs. the San Antonio Spurs. But one fan at TD Garden took it way too far.

The fan, who reportedly has since been arrested, tossed a drink onto the court that came dangerously close to hitting players on the Spurs' bench.

Watch the incident below:

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Obviously, the act was inexcusable. And Celtics head coach Brad Stevens went out of his way to apologize to the Spurs after the game for what took place.

"I'm sure the Celtics have already addressed this as an organization, but if not, I apologize to the Spurs for what happened out of the stands and that can being thrown. I told [Gregg Popovich] after the game I'm really sorry they had to experience that. I hope that person's not allowed in an NBA arena again."

Celtics forward Gordon Hayward was equally unhappy with what unfolded.

"We can’t have that. I’ve never had that happen, I don’t think," he said. "But certainly, no matter what happens on the court, we can’t have anybody throwing stuff from the fans. It’s not what it should be. So yeah, I definitely don’t appreciate that. I love our fans, love the passion that they bring. They certainly bring a lot of energy, but we’ve got to try to stay away from that.

"I heard it. I mean it was like almost a full can. I don’t know what happened after that. Everything happened really fast as far as Kemba being ejected. It’s an unfortunate part of the game for us, but we’ve got to move on from it."

Fortunately, no one was hit by the can and TD Garden staff acted swiftly in identifying and removing the offender.

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