Juan Martin del Potro ended Rafael Nadal's bid for an unprecedented second Olympic singles gold medal in a thrill-a-minute semifinal, then celebrated as if the title were already his, kneeling to kiss the court before leaping into the stands.
Del Potro, who earned a bronze for Argentina four years ago, will add a silver or gold to that after advancing to the Rio de Janeiro Games final by coming back to stun 2008 champion Nadal 5-7, 6-4, 7-6 (5) in more than 3 hours Saturday.
"Both of us," Nadal said, "played a very high level."
Using the same ferocious forehands that carried him past No. 1 Novak Djokovic in the first round a week ago, 2009 U.S....