Argentina, Croatia tied in Davis Cup
Del Potro defeated Karlovic 6-2, 7-6 (7), 6-1.
Need the scores from any match played in today's tournaments? Results
Nalbandian said he intended to play despite speculation captain Martin Jaite might replace him with Juan Monaco. Reverse singles are Sunday.
The 23-year-old Cilic wore down the 30-year-old Argentine, finally winning on his third match point.
Spain 2, Austria 0
Almagro, ranked No. 12, opened the best-of-five series on Friday by beating Jurgen Melzer 6-2, 6-2, 6-4 on an outdoor clay court. Ferrer, ranked No. 5, followed by defeating 139th-ranked Andreas Haider-Maurer 6-1, 6-3, 6-1.
The winner of this series will advance to September's semifinals against France or the United States.
Serbia 1, Czech Republic 1
Tipsarevic, who has climbed to a No. 8 ranking, faced a match point at 5-6 and two more at 6-7 in the fifth set. But he served well to remain in the match and won in more than five hours.
Doubles in the best-of-five series is Saturday and reverse singles is Sunday.
The winner advances to the semifinals in September. Serbia, without top-ranked Novak Djokovic, is looking to make a third straight semifinal.
Information from The Associated Press was used in this report.
Copyright 2012 by The Associated Press
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