Actually, if you watch their matches again, I think you'll find that the balance was pretty tight in all of them, could have gone either way, although I did not see their first match, so I don't know about that one, I understand Federer was ill in that game. I don't think Federer is particularly concerned about Nadal because Nadal has the type of game that allows Fed to control a lot of the points and get into the match, it's just that Nadal gets so much back, so Federer has to watch his consistency and placement. There is no fear that he will be blown away be Nadal, in the way Hewitt and Sampras were in the US Open finals by Federer and Safin respectively. Nadal does not have that type of game, it is more of a scrambling and retrieving game. I think Federer will be more concerned about someone like Berdych in the future. Berdych is big, he can move and he has the firepower to hurt Federer, also, mentally, he already pretty much thinks he is the best or at least will be, he has that confidence. Of course he still needs to develop some more, but I see him being a real problem for Federer in the future if he continues to progress. Time will tell.