Everyone has been so quick to call Greninja shit all day; but has anyone ever stopped to think that maybe Ash is the jobber?

Every time Greninja got hit, Ash looked like he was in more pain than it. It's highly possible that Greninja was prepared to go on; but Ash was to exhausted to continue, so he passed out.

We don't really know how Synchro-evolution works, but I imagine that the trainer's stamina is a huge factor, and Ash has never been in a situation that pushed his Stamina like that, since Greninja mostly swept.