BUENOS AIRES, Argentina -- Argentina lost the Davis Cup doubles on Saturday -- falling behind 2-1 against the Czech Republic in the semifinals -- and also lost Juan Martin Del Potro for Sunday's deciding singles.
Del Potro defeated Radek Stepanek on Friday in singles playing with an inflamed left wrist on his non-racket hand. He said afterward he was in pain and playing with only half of his arsenal of shots.
Del Potro's doctor warned him that his wrist was at risk if he played in the Davis Cup. Wrist problems ruled out the 2009 U.S. Open champion for most of the 2010 season.
On Saturday, Argentina captain Martin Jaite said del Potro was being replaced by doubles player Carlos Berlocq, who will face Tomas Berdych in Sunday's first reverse singles.
Berdych and Stepanek defeated Eduardo Schwank and Berlocq 6-3, 6-4, 6-3, and put their team on the brink of returning to the final for the first time since 2009.
Berdych will be favored to secure victory against Berlocq, who was making his cup debut. Stepanek and Juan Monaco were scheduled to meet in the last match on the outdoor clay court.
Berdych dismissed any worries about playing three days in a row.
"My physical aspect is fine," he said. "I won two tough matches, but I'm here to be ready for three days. Winning two matches gives me a lot of confidence."
Argentina is trying to reach its fifth final. It has lost a record four finals, including last year against Spain. The Czechs won as Czechoslovakia in 1980. They lost in the 2009 finals to Spain.