Don't panic! Two of Stan's wins have been on clay and two on hard court - the first of these being in Miami in 2006 and the second, and most recent, at last year's USO where, unfortunately, Andy fell apart spectacularly in the 3rd and 4th sets, although it was later revealed that he was suffering from a virus. Hopefully this time round he'll be buoyed up after his wins in Bangkok and Japan plus his determination to take over Federer's No.3 ranking. Also Wawrinka is without a coach, having recently parted company with Peter Lundgren. Andy is without a coach too, but this is a new situation for Wawrinka, so how he deals with it could be a factor in this match.
Totally agree with you Aileen. This is a different Andy and a different Stan.