I just saw that. Insane. I wonder if Falla will choke on serve for the match. I can see it happening.
I've seen various matches where he's had that happened, guy is good enough to get through it sometimes.
Federer gets credit for being Federer in that situation but that's a big part of what separates players in this sport beyond the obvious differences in talent: the ability to close matches and perform under pressure. That's as much of what makes guys like Federer and Nadal special as their abilities, particularly in Nadal's case.
If Falla can't find a way to win this set, I see Federer steamrolling in the 5th... 6-1 or 6-2, something like that.