George Foreman def. Michael Moorer – 1994:
George Mason’s aforementioned Final Four run was an unreal run, but George Foreman’s improbably heavyweight title run was an all-time upset by a George of a different kind.
Still competing at 45 years old, Foreman had lost his previous bout to Tommy Morrison and was in no position to receive a title shot. He did due to his lengthy resume and name recognition, however, facing Michael Moorer on November 5, 1994.
19 years the junior to his opponent, Moorer out-boxed Foreman for nine rounds. However, Foreman came alive to land a perfect right on Moorer’s chin. A knockout win followed, and Foreman set some insane records in the process. He became the oldest fighter to win the heavyweight title and set a new record for the longest time in between title runs.