CAPTAIN AMERICA VS. IRON MAN
This is inevitable. This is going to happen in Captain America: Civil War. Otherwise, what would be the point of signing Robert Downey Jr. to appear in the film?
In the Civil War comic, Cap and Iron Man were diametrically opposed to each other over the SRA. When the two men eventually met in battle they didn’t hold back. Cap even cheated by pretending to be willing to negotiate with Iron Man before he temporarily disabled his armor. The resulting fight was brutal and it didn’t go well for Cap.
Chris Evans and Robert Downey Jr. are probably really looking forward to this, as a Captain America vs. Iron Man fight scene sounds like it could be really fun. The only question is whether that fight will be saved for the end of the film or if Cap and Iron Man will throw down throughout the movie before the final battle.