(via Getty.)
Time and time again, we like to convince ourselves that a champion is unbeatable. Anthony Pettis was unbeatable, except for when he was defeated by Clay Guida in his first UFC appearance, then again by Rafael Dos Anjos at UFC 185. Renan Barao was a pound-for-pound king, until he got torched by a massive underdog fighting on short notice. Cain Velasquez was unbeatable and the supposed greatest heavyweight of all time, except for when he was KO’d by Junior Dos Santos in just over a minute a handful of fights ago.