Rivera needs just 21 seconds to smash Caceres

Francisco Rivera almost punched the afro off of Alex Caceres' dome.

Mere moments into their bout at UFC Fight Night 68 on Saturday night, Rivera, who had already landed a few hard shots, absolutely blew Caceres' doors off, flooring "Bruce Leeroy" with a vicious left hand to the jaw, before finishing him off with a series of coffin nails just 21 seconds into the opening round.

Wow. Just ... wow.