Britain's Andy Murray prepares to serve as he is watched by his coach Ivan Lendl, top second left, and Darren Cahill during his exhibition match against Argentina's David Nalbandian at the Kooyong Classic in Melbourne, Australia, Friday, Jan. 13, 2012. (AP Photo/Mark Baker)
Rafael Nadal, the No. 2 seed, dispatched David Nalbandian in straight sets before experiencing a severe leg cramp during Sunday's action at the U.S. Open. He reacted to the pain (below) during his post-match news conference.
Switzerland's Roger Federer celebrates defeating Argentina's David Nalbandian in their match at the All England Lawn Tennis Championships at Wimbledon, Saturday, June 25, 2011. (AP Photo/Anja Niedringhaus)
Argentina's David Nalbandian reacts after he defeated Russia's Mikhail Youzhny during their Davis Cup World Group quarterfinal tennis match in Moscow, Russia, Sunday, July 11, 2010. (AP Photo/Misha Japaridze)