It might be time for Chris Evans to invest in a bigger t-shirt.
Not that we don't appreciate his bulging biceps, but if his muscles get any bigger, he's going to Hulk out and tear that S.H.I.E.L.D. shirt right open!
The actor was spotted on the set of "Captain America: The Winter Soldier" yesterday in Washington, DC ... where he filmed scenes with Scarlett Johansson and Anthony Mackie, who will play The Falcon.
The movie won't hit theaters until next April, but you can check out some footage from the set below, courtesy WJLA ABC 7:
The movie is part of Marvel's Phase 2, which (along with "Thor 2" and "Iron Man 3") will lead up to "The Avengers 2."
Earlier this week, Marvel also unveiled the first look at their new TV show "Agents of S.H.I.E.L.D." -- click here to check out the extended trailer.