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Two and a Half Men star Jon Cryer was injured on Sunday during the Nautica Malibu Triathlon, forcing him to withdraw from the race.

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The annual event featured an ocean swim, an 18-mile bike course and a 4-mile run. Cryer was scheduled to complete all three legs, but after his nasty tumble on the bike course, he headed straight for the medical tent to tend to his bloodied and bruised limbs.

The Malibu Triathlon, now in its 26th year, benefitted Children's Hospital Los Angeles and raised a reported $1.17 million for their pediatric cancer research program.

Other participants included Ellie Kemper, Rainn Wilson and James Marsden along with CBS employees like Senior Vice President of Marketing for CBS Studios International Teri Fleming, Director of Research at CBS Studios International Max Flisi and Director of Human Resources DJ Duronslet.

Marsden revealed that even though the race is for Children's Hospital, that doesn't make it child's play.

"As soon as the gun goes off, you get competitive," said the X-Men star, who admitted to overexerting himself.

Likewise, The Office stars Ellie Kemper and Rainn Wilson made no attempt at hiding their ambitions.

"I'm literally going to take [Kemper] down," Wilson joked. "I'm going to take her down from behind, wrap up her legs, she's gonna hit the deck and I'm going to cross that finish line."

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