New obstacles loom for Federer (AP): "The men's tennis tour moves to clay next week, and for Roger Federer, the surface looks more treacherous than ever. Playing on dirt is all about grinding and grunting and groundstrokes -- the sort of challenge that suits someone like, say, Guillermo 'Willy' Canas. If Federer can't beat Canas on a hardcourt, how will he beat him at Roland Garros?"