Published: Oct 26, 2012 4:29 PM EDT
Updated: Oct 27, 2012 6:31 AM EDT

WASHINGTON (AP) - Rob Riggle will be with thousands of runners at the beginning and the end of the Marine Corps Marathon this Sunday in Washington. Not as a runner, but as the grand marshal.

His job is to fire the starting gun and hold the tape at the finish line.

Riggle has been in the Marines for 22 years, most recently with the reserves. But he's put in his retirement papers so he can concentrate on making movies like "The Hangover."

While in Washington, Riggle also taped a sketch and his picks for "NFL Sunday." Riggle admits he took the job more for the comedy. He's not very good at predicting the winners, but he says he's not losing any sleep over it.

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