Ryan Harrison Tantrum: American Tennis Player Causes Scene During U.S. Open Loss (VIDEO)

In the eyes of the U.S. legal system, Ryan Harrison is an adult. Still, the American had many people comparing him to a child throwing a temper tantrum as a result of his antics during his opening match at the U.S. Open on Monday.

Playing against the hard-serving Marin Cilic, "Mr. Cranky Pants," as Harrison was described by tennis analyst Mary Carillo, threw his racquet several times during his match, and at one point even kicked a ball into the stands out of frustration. The crowd, generally very supportive of homegrown players, eventually turned on him as well.

And in losing in three straight sets to Cilic, Harrison proved that it isn't only his attitude that hasn't matured.

As Ed McGrogan described the scene on Tennis.com, "After Harrison stoned a bread-and-butter volley down 5-6, he wound up and kicked the green sphere into the crowd, accurate and with good distance. It would have been called "good" in pro football. None of which can be said about Harrison's tennis today."

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