Khloe In Krisis! Inside Her Boyfriend Tristan Thompson's Rage-Filled Past

Kim Kardashian is used to Kanye West's volatile temper, but RadarOnline.com has learned she isn't the only one in the family dealing with a partner who flies off the handle!

It turns out that Khloe Kardashian's NBA star boyfriend Tristan Thompson has his own secret past filled with rage-fueled incidents!

"Back in high school he was known for his fiery temper on the court — once he even walked out on the coach in the middle of a game," explained a source.

Before he became a big NBA-basketball star with the Cleveland Cavaliers, Thompson, 25, was a promising junior playing on the St. Benedict's Prep basketball team in New Jersey.

"He was kicked off the team for public insubordination," Thompson's then head coach, Dan Hurley, revealed in an interview.

"I just know that I'm not going to be his coach and that's about it," said Hurley, who kicked Thompson off the team after the two got in a heated exchange during a game.

"Tristan insists he's calmed down a lot since then, but when things don't go his way, he's still known to throw a tantrum," a source told Radar.

As a result, added the source, his 32-year-old reality star girlfriend knows to stay away when he's in a bad mood: "Khloe knows not to push his buttons!"

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