Chris Evans and Scarlett Johansson have been friends for a while (five films!), which means the opportunities for pranks are endless. Especially when set up by that master of practical jokes, Ellen DeGeneres. ScarJo appeared on Ellen to talk Avengers, and while she was in the middle of mocking her many male co-stars, Evans got her good. Add that to the list of things he'll have to apologize to her for.
But don't worry, ScarJo got her revenge in a shameless game of Avenger? I Hardly Know Her. Well played, Ellen.