Serbia's Djokovic out of opening Davis Cup singles
Novak Djokovic has withdrawn from Serbia's opening singles match in the Davis Cup semifinal against the Czech Republic, citing a case of gastroenteritis.
A statement on the Davis Cup website says Djokovic has been replaced by 47th-ranked Victor Troicki, who will play Radek Stepanek on Friday.
It is unclear whether Djokovic will be fit to play in Saturday's doubles match or the reverse singles on Sunday.
The No. 2-ranked Djokovic has just traveled to Belgrade from the U.S. Open, where he lost to Rafael Nadal in four sets in Monday's final.
Serbia's Janko Tipsarevic plays Tomas Berdych in the second singles match.