(Reuters) - List of U.S. Open men's singles champions (since tennis turned professional in 1968):
2015 Novak Djokovic (Serbia) beat Roger Federer (Switzerland) 6-5 5-7 6-4 6-4
2014 Marin Cilic (Croatia) beat Kei Nishikori (Japan) 6-3 6-3 6-3
2013 Rafa Nadal (Spain) beat Djokovic 6-2 3-6 6-4 6-1
2012 Andy Murray (Britain) beat Djokovic 7-6 7-5 2-6 3-6 6-2
2011 Djokovic beat Nadal 6-2 6-4 6-7 6-1
2010 Nadal beat Djokovic 6-4 5-7 6-4 6-2
2009 Juan Martin del Potro (Argentina) beat Roger Federer (Switzerland) 3-6 7-6 4-6 7-6 6-2
2008 Federer beat Murray 6-2 7-5 6-2
2007 Federer beat Djokovic 7-6 7-6 6-4
2006 Federer beat Andy Roddick (U.