UFC superstar Luke Rockhold kicked so much ass this weekend, his foot exploded. 

Well, it certainly blew the hell up. 

Take a look at video of Luke's insanely swollen and bruised right foot -- which he earned during Saturday night's dominant TKO victory over David Branch at 'UFC Fight Night' in Pittsburgh. 

Maybe put some ice on it?

The good news ... Rockhold seems pretty comfortable recovering while chillin' at a rooftop pool in the Steel City.

Could be worse ... could be David Branch's face.