The first day of the 2012 Davis Cup semifinals has come to a close, with Argentina and the Czech Republic knotted in a 1-1 tie in their best-of-five matchup in Buenos Aires.

Argentinian Juan Martin del Potro, ranked No. 8 in the ATP Rankings and a former U.S. Open champion, defeated the Czech Republic's Radek Stepanek, 6-4, 6-4, 6-2 in Friday's early match. The nightcap saw No. 6 Tomas Berdych come from behind to topple Argentine Juan Monaco (No. 11) in a grueling five-set match, 6-4, 4-6, 1-6, 6-4, 6-4.

Saturday's matches will feature doubles action, with Argentina's Carlos Berlocq and Eduardo Schwank taking on the Czech Republic's Lukas Rosol and Ivo Minar. Sunday's singles matches will flip Friday's script, pitting del Potro against Berdych, while Monaco will battle the 40th-ranked Stepanek.

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