Has a fighter ever lost the 'formality' rematch or career defining win?

[ICB]

What I mean here is when a fighter takes his legacy fight, either a rematch against a shock loss, or a fight against a legend when the legend is supposed to be past his prime and the outcome a formality, has there ever been a case where the favoured fighter has lost and if so who.

Examples I can think of formality wins are Lennox Lewis avenging his shock losses to Rahman and McCall, and winning his career defining fight over Mike Tyson, an important fight for his resume, but one that was expected at the time to be a routine job.

Other examples are Wlad's return win over Lamon Brewster, Calzaghe's win over Roy Jones Jr etc.

Going back in history you could mention Ray Robinson against Randy Turpin for example.

So are there any examples in fight history where the guy who shocked the world by upsetting a superstar in the first fight against all odds did it again in the rematch, or a case where the ageing, finished great spoilt the coming of age party for the new lion by beating him when not expected to?

Anyone got any famous examples?

Well for your first question, i think Junior Jones beating MAB was a big upset. And he proved it was no fluke beating him again over 12 rounds.

As for your 2nd question well Larry Holmes was 42 years old, and Ray Mercer was supposed to be an upcoming star. And Larry Holmes gave Ray Mercer a boxing lesson.

And im pretty sure he was the favorite from what i remember, the commentator saying. I'd have to pull out my Larry Holmes career set to make certain, but im pretty im right.