3. Matt Serra (+550) Upsets Georges St. Pierre UFC 69
I have to admit I assumed either this bout or Holm over Rousey would be the #1 entry. But that is just not the case. At the time it happened however, this was the biggest upset in UFC championship history.
Matt Serra had won the 3rd season of the Ultimate Fighter. On that particular season they changed the format, bringing in fighters with UFC experience and granting a title shot to winner. Few gave Serra a chance against GSP after he won the welterweight TUF tourney however.
But at UFC 69 Serra punched himself into the record books at 3:25 of the 1st round. GSP would avenge the loss and take his title back a year later.
