No it's not mixed doubles line up. I just got amazed by the similarity between Fed-Nadal and Graf-Seles. 1) In both cases, one right handed player with excellent serve and all time best forehand dominates the tour like anything. Then a left handed upstart comes and topples the empire. They play some great finals, including GrandSlams. The left handed player first takes over clay and slowly expands into other surface as well. 2) There are differences too. Graf dominated Seles in early years whereas Nadal was always leading head to head against Fed. Now the tragedy. Seles was attacked by Gunther Parche's knife and the rivalry got terminated just when she extended her first win over Graf in hard court. Everyone still wonders what would have happened if there was no stabbing, would Seles went on and on or Graf could have turned over. Is it only me that thinks that Federer-Nadal is the answer. That we are in a mirror of that rivalry. After dominating tour till 2007 (including wins over Nadal in hard and grass) Federer finally wilted in 2008 which is still going on.