It is only 2 days as he plays for Chile on thursday and i can't see the manager letting him do anything on a match day
Sanchez has nothing else to do. It's between the clubs now.
They can sign everything on deadline day "subject to a medical" and Sanchez can do the medical after the match or even when he comes back.
This will probably go down to the wire as Arsenal want to squeeze out as much as they can and we want to pay the least amount possible.