Federer lost first set 5-7 after being up 5-3 with him serving for the set.
Nadal is playing great tennis ATM, so If Federer manages to beat him I'm sure he is THE best tennis player of all time, I know many has him as the GOAT already but he HAS to beat Nadal in a French Open Final especially since Nadal is the number one ranked in the World and doesn't want to lose against Federer at the Frech Open, particularly in a Final.
If Federer wins Nadal will be in a LONG LONG slump....