Despite the fact that their match included blood (in the PG-13 era!), one of the most damaging and humiliating moments in Brock Lesnar's career came during his first match back in the WWE after he returned in 2012. Coming home after his impressive UFC tenure, Brock may have dominated his Extreme Rules match with John Cena, but still lost. That loss came after being punched in the face with a steel chain and receiving an AA onto steel steps, but the lengths Cena went to to take him down made it no less embarrassing for Lesnar. Paul Heyman cleverly used Brock's diverticulitis to explain the way this match ended years later, but it wasn't until WrestleMania 30 that the WWE made things right.