YES, you can only choose one, come on guys, forget the drama and everything around the match just pure tennis on the court.
Roger Federer vs Rafael Nadal Rome Masters 2006
I am a huge Federer fan and although he lost, I still appreciate the high quality tennis shown from both men. It was much better tennis than they showed in their Wimbledon 2008 final.
Also if anyone can find a high quality link for this match please, pm me the link or post it here.