Originally Posted by philosophicalarf
I think he has some repeat small injury that keeps flaring up.
No, he's been looking lost on the court since last summer, he wouldn't have kept playing during all that time in singles and doubles if he was injured. And he really insisted in Melbourne after his defeat to Istomin on the fact that he is perfectly fit, joking that there was at least one positive in this disaster.
He did injure his wrist during his doubles match in Melbourne then, so maybe it was still bothering him yesterday, I have no idea, but it doesn't explain this terrible slump.
He sounds in his recent interviews like he can't explain it either, just says that his game is a giant mess, he has completely lost control of his serve and his groundstrokes and can't play two shots in the court in a row to save his life, etc.