Well, we saw Nadal have a mighty struggle in his opening match against John Isner. He was pushed all the way and was forced to play five sets. Absolutely incredible considering that he had never previously played a five set at Roland Garros. It had been four sets at most. He has been struggling a lot this year and I would not be shocked if he was beaten some time before the final. Soderling did it couple years ago and with a bit more skill than serve you can do that. Isner was unable to do because he is all about big serve and forehand. Even if Nadal reaches final, there's still a good chance Djokovic won't. He has been walloping everybody on his way and probably will get to last eight easily but after that who knows. He has never been past semies in this tournament and I think odds 1.85 are very good for either of Nadal of Novak to fail to make the final.