Manny really doesn't have anything to lose. He's going to make an insane amount of money and so what if he loses, he already got put to sleep by JMM so a loss to Floyd isn't really going to make people think less of him. And of course his fans will go to their graves saying that Pac was washed up when Floyd beat him, and Pac would have killed Floyd if they fought 4 years earlier. He's got 5 loses on his record, a 6th loss isn't going to make anyone love him any less.

Floyd's earning power and legacy really hinges on that undefeated record, because people hate Floyd. The second he loses to anyone, people are going to go "see, he was never good, he just fought hand picked stiffs and when he finally fought someone good he lost."