(CNN) -- They played in the U.S. Open final Monday but both Rafael Nadal and Novak Djokovic were back in action for their countries Friday. They both won, too, overcoming fatigue, jet lag and a change of surface. Nadal, who beat Djokovic in New York to claim his 13th grand slam title, prevailed 6-0 6-0 6-4 over Sergiy Stakhovsky -- Roger Federer's conqueror at Wimbledon -- on his favored clay. He boosted his Davis Cup record in singles to a near invincible 21-1, with his lone reverse coming in his first outing against Jiri Novak in 2004. Nadal hadn't played in the competition since 2011, opting to skip proceedings in 2012 even before his season was ruined by a knee injury.
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Rafael Nadal crushes Sergiy Stakhovsky in his return to Davis Cup duty for Spain
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Nadal didn't have much time to prepare for the series after winning the U.S. Open Monday
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Serbia's Novak Djokovic also made the quick turnaround and thumped Vasek Pospisil
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The Czech Republic leads Argentina 2-0 in their Davis Cup semifinal in Prague
"Today is another victory after a long year and every victory is important," Nadal told the @placeholder website.