That was a very smart match from Juan Martin. He varied his pace with slices and softer shots and then went for it at the right time when he got a good ball with which to pound the forehand. He hung in there when he was down 3-0 in the third, didn't panic and gradually worked his way back, and you could see Nole getting flustered. Big, big heart from Del Potro. Congrats to his fans, condolences to the Nole fans. He played well.
Unforced errors are always going to be there on this slow high bouncing court, when you have to paint lines to get winners. Del Potro played better when it mattered.
Let's see if Juan Martin has something left in the tank tomorrow against Nadal. I personally don't think Nadal could have stayed with either Nole or Juan Martin today. But tomorrow? Now with the effort Del Potro had to give today, Rafa has a good chance.