Clydey - lots of top sportsmen play much of their careers carrying one niggling injury or another. Rafa's known to have issues with his knees, and there's nothing wrong with getting treatment for it.
Yes it disturbed Andy's concentration, but I don't believe that was the reason for Nadal to call the trainer. He was playing, his knee started to bother him, and he called the trainer before it interfered with his game. Nothing wrong with that at all. Andy needs to learn to deal with it.
And if he wins this, Andy will have won 9 out of 10 against the top 3. Even if you want to discredit this one, then making the argument that Andy doesn't regularly beat the top players outside the slams holds no water whatsoever.
I'm not saying that there's a problem with him calling for the trainer. I'm saying he looks entirely uninhibited. You do not break the serve of one of the best players in the world 4 times consecutively if you're injured.