Once?:
3/2012 SF Australian Open Hard Rafael Nadal Roger Federer 6-7(5) 6-2 7-6(5) 6-4
47/2011 RR A ATP World Tour Finals Hard Roger Federer Rafael Nadal 6-3 6-0
12/2011 SF Miami Masters Hard Rafael Nadal Roger Federer 6-3 6-2
47/2010 F ATP World Tour Finals Hard Roger Federer Rafael Nadal 6-3 3-6 6-1
4/2009 F Australian Open Hard Rafael Nadal Roger Federer 7-5 3-6 7-6(3) 3-6 6-2
26/2008 F Wimbledon Grass Rafael Nadal Roger Federer 6-4 6-4 6-7(5) 6-7(8) 9-7
45/2007 SF Tennis Masters Cup Hard Roger Federer Rafael Nadal 6-4 6-1
26/2007 F Wimbledon Grass Roger Federer Rafael Nadal 7-6(7) 4-6 7-6(3) 2-6 6-2
45/2006 SF Tennis Masters Cup Hard Roger Federer Rafael Nadal 6-4 7-5
26/2006 F Wimbledon Grass Roger Federer Rafael Nadal 6-0 7-6(5) 6-7(2) 6-3
9/2006 F Dubai Hard Rafael Nadal Roger Federer 2-6 6-4 6-4
12/2005 F Miami Masters Hard Roger Federer Rafael Nadal 2-6 6-7(4) 7-6(5) 6-3 6-1
13/2004 R32 Miami Masters Hard Rafael Nadal Roger Federer 6-3 6-3