Chris Evans and Chris Pratt didn't attend Super Bowl XLIX merely to root for their home teams and settle their friendly (and charitable) wager. No, the stars of Marvel's Captain America and Guardians of the Galaxy also went to Phoenix to photobomb unsuspecting football fans.

Host Jimmy Fallon enlisted the actors for an installment of "Tonight Show Celebrity Photobomb," in which the trio stealthily -- and sometimes not so stealthily -- crept up behind fans posing on the NBC Super Bowl Red Carpet. What began as simple solo pop-ups quickly escalated with the addition of stunts and props, including a seemingly innocent hoagie that Pratt turned somewhat obscene (see below).

And if you had any doubt about Captain America's athletic prowess -- or Star-Lord's trust in that athletic prowess -- skip to about 1:53 in the video below.