by Mark HastyFiled under: Davis CupJust how hurt is Rafael Nadal, anyway? He's not defending his Wimbledon title because his knees weren't at 100 percent. Now Nadal has been left off of Spain's Davis Cup team for next month's matches.Spanish coach Albert Costa says Nadal "is not well." This was obvious to anyone who watched his exhibition match with Stanislas Wawrinka, a match which Nadal lost. There is no real shame in losing to Warwrinka, who just gave Andy Murray ...