not sure... I can only guess, but from what I've witnessed, it seems like when Robby isn't playing well, it's either because he's not feeling well physically, or it's because he just isn't focused out there... I think he's one of those players that can be too aware
of what's going on around him, and he let's too many different things distract him at the same time. Once he starts doing that in a match, it's really hard for him to knock it off, because he only adds more for himself to think about as he loses momentum, etc. As cliche as it sounds, of all people, Robby really just needs to focus on one point at a time, and make sure he's doing all he can to put himself in good position to win each point, and if he loses a point, to think only about being in the next point. When he does that, that is when he is most successful.
Robby plays Rhyne Williams in the first round at Dallas.