Quote Originally Posted by Gyrokai
But we are not talking Tyson, we're talking Biggest Undefeated Fight Ever.

And that easily goes to Ali Frazier's Fight of the Century.
The question (poorly worded as it was) is statistically, what is the biggest fight between undefeated fighters; i.e. Jofre/Caraballo were between themselves unbeaten in 99 fights.