Rafael dos Anjos (25-7) had rattled off five straight victories in one of the most impressive streaks in UFC history before Eddie Alvarez (27-4) shocked the world to take home the 155-pound crown.
A massive underdog against the champ, he took a few heavy strikes early, but caught RDA right on the button to wobble his legs and send him backpedaling toward the cage.
Alvarez jumped on top and wouldn't give up, forcing referee Herb Dean to end the bout and hand the heavy-hitting Alvarez the belt.