Leading 2-1 Sunday, Nadal, who has never lost a match at the French Open, clenched the semifinal win with a 6-4, 6-0, 6-4 victory versus Andy Roddick of the USA.
"I played an almost perfect match," Nadal told reporters. "I shocked myself with some of the winners."
"I don't know what else I could have done there," Roddick said. "In my opinion, he's the best claycourter of all time."
Argentina relied heavily on its own rising star as 19 year old Juan Martin Del Porto won both of his singles matches easily to propel his country into the Davis Cup final.
Del Porto, who stands 6 feet 6 inches and won four hardcourt tournaments in a row during the summer, gave Argentina a 3-2 win by defeating Russia's Igor Andreev 6-4, 6-2, 6-1 in the fifth rubber.
“Last night I couldn't sleep and now I'm living the dream for sure,'' Del Potro said. “I want to treasure
this moment because I don't know if it will happen again.'”
Argentina, seeking its first Davis Cup title, will host Spain in the final November 21-23 at Cordoba on a fast surface most likely in an attempt to gain an edge on claycourt king Nadal. Nadal at age 18 helped Spain to win its second Davis Cup title in 2004.