Highly regarded UFC champion Amanda Nunes was recently defeated in what many in the MMA community called the biggest upset of all time. She was a 10/1 betting favorite.

One lucky punch has proved time and again that favorites don't always win in boxing. These are 5 of the sport's biggest upsets.

Wednesday was the 45th anniversary of Muhammad Ali's (Cassius Clay for this fight) upset victory over Sonny Liston in Miami in 1964. Ali was such an underdog that the New York Times boxing writer ...

This is one of the biggest upsets of all time. Mike Tyson was the undefeated heavyweight champion in 1990 and was thought to be indestructible.

And as we found out 10 days ago when Andy Ruiz stunned the world by knocking out favored champion Anthony Joshua, boxing is still full of characters and storylines and upsets worth pursuing.

One lucky punch has proved time and again that favorites don't always win in boxing. These are 5 of the sport's biggest upsets.