CLEVELAND -- Late in the fourth quarter of Game 6 of the NBA Finals on Thursday night, Stephen Curry did something he so rarely does: The Golden State Warriors star lost his cool.

After picking up his sixth foul of the game against the Cavaliers in Cleveland, Curry — clearly frustrated with the foul that was called and the overall outcome of the game — threw his mouthpiece toward the stands. It hit a fan sitting courtside, and Curry was ejected after picking up a technical foul. It was the first ejection of his career.

See the moment again in slow motion:

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Being the stand-up guy that he is, Curry went over to the fan, apologized and shook hands with him, but the heightened level of frustration from such an even-tempered individual said it all.

Turns out that fan was Andrew Forbes, son of a Cavs minority owner.

"He had every right to be upset," Warriors coach Steve Kerr said after the game. "He's the MVP of the league, he gets six fouls called on him, three of them were absolutely ridiculous."

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Was Kerr upset with Curry for letting his frustration show?

"I'm happy he threw his mouthpiece," Kerr said with a laugh. "He should be upset."

Stephen Curry of the Golden State Warriors shakes hands with fans after throwing his mouthguard in the fourth quarter against the Cleveland Cavaliers in Game 6 of the 2016 NBA Finals at Quicken Loans Arena on June 16, 2016.

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