Argentina's injured and emotional Juan Martin del Potro beat Radek Stepanek in the opening match, and the Czech Republic's Tomas Berdych evened the Davis Cup semifinal by topping Juan Monaco in the second match Friday.
Del Potro, told by doctors not to play because of an inflamed left wrist, beat Stepanek 6-4, 6-4, 6-2, and then broke down crying as he addressed fans chanting "Ole! Ole! Ole!" at the outdoor clay-court venue.
"In truth, it wasn't easy to play," Del Potro told the crowd. "You can see how I suffered playing. I did it for all of you. Playing here means so much for you, for the country, for Argentine tennis — for everyone and me too. I want to thank you for the love and support you have always shown me."
Berdych later rallied to edge Monaco 6-1, 4-6, 1-6, 6-4, 6-4, leveling the contest before the doubles Saturday and reverse singles Sunday.
Stepanek tried to work to Del Potro's backhand — where the Argentine uses his left hand on the two-hand shot. Del Potro wound up with only three winners off his backhand compared to 11 for the Czech, an indication he was playing at a disadvantage.
"There is always some pain," Del Potro told the crowd, which included soccer great Diego Maradona. "We all have some pain — some more than others. The important thing is to try to play and do your best."
Argentina is trying to reach its fifth Davis Cup final. It has lost all four previous finals — a record — including a year ago against Spain.
Spain took a 2-0 lead against the United States in the other semifinal. A Spain-Argentina final would be played in Buenos Aires. The Czechs will be the home team if they reach the final.
Del Porto said Thursday he would not have played were this an ordinary tournament.
"I think everyone saw how I played," Del Potro said. "It was very difficult playing like this. My serve helped, the forehand helped, but when you can't do damage with every shot, it's difficult. .... And the effort I put out is much greater than usual."
Stepanek, who complained about the crowd noise at Parque Roca, suggested Del Potro was exaggerating the injury. Speaking in Czech, he said Del Potro looked "absolutely healthy." Stepanek said Del Porto's tears at the end seemed "blown out of proportion."
Told about Stepanek's comments, Del Potro replied: "I wish I were perfect. I'm surprised to hear what he said, because it's not what he said to me."
Stepanek converted only one of eight break-point chances. Del Porto made good on five of seven.
"I had my chances and didn't come through," Stepanek said.
Leading 4-2 in fourth set, Moncao seemed to be en route to victory. But he promptly slumped to another defeat by Berdych, who reached the U.S. Open semifinals before losing to eventual champion Andy Murray.
The Argentine pair of Carlos Berlocq and Eduardo Schwank are scheduled to face Ivo Minar and Lukas Rosol in doubles Saturday.
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