ok, i'm gonna make a guess here...
it looks bad, but :
- he didn't practice, or at least not a full practice on location, he wasn't hanging around in the "allées" at all, so i bet he spent most of his time seeing a doctor and resting the ankle.
- he's still scheduled tomorrow
so : i think it's not THAT bad, and with the proper care he can probably play, now the question is, is he gonna take the risk to make it worse or not ?! i think he will, because if he really didn't feel like it he would have pulled out by now.
i can be wrong of course, but i was a gymnast, i've twisted both my ankles pretty badly multiple times, i've been where he is, and i took my chances... and it has always been for the better ! i wish him the same on that one !