(Adds last match, quarter-final opponent)
By Gennady Fyodorov
MOSCOW, Feb 10 (Reuters) - Russia beat Serbia in the Davis Cup when an unwell Novak Djokovic retired from his match against Nikolay Davydenko, handing the home team an unassailable 3-1 lead in their first-round tie on Sunday.
The 2006 champions and last year’s runners-up, will host the Czech Republic, who beat Belgium 3-2, in the quarter-finals in April.
Australian Open champion Djokovic had won the first two sets against Davydenko and was 3-0 up in the third despite being way below his best and often struggling for breath after suffering from flu symptoms in the last few days.
However, Davydenko staged a miraculous recovery to win the third set 6-4, after which the Serbian decided to quit.
“I stopped because I didn’t want to risk my health,” Djokovic told reporters after showing up for a news conference more than an hour after his match.
“I didn’t go to hospital after all but still, I was feeling very dizzy. I was losing a lot of energy. It’s not easy to play when you have a virus infection.”
A Serbian team spokesman had earlier said Djokovic was taken to a local hospital suffering from exhaustion.
The home team had led 2-0 after sweeping both singles matches on Friday but Djokovic kept alive Serbia’s hopes when he teamed up with Nenad Zimonjic to win Saturday’s doubles.
With Serbia number two Janko Tipsarevic also sidelined by a stomach bug and ankle injury, the visitors gambled on the unfit Djokovic to challenge the Russian number one.
“It was my decision to play the match,” said Djokovic.
The world number three, cheered on by a small but vocal Serbian contingent at Moscow’s Luzhniki arena, broke Davydenko in the 12th game to take the first set 6-4.
After losing his serve in the opening game of the second set, the 20-year-old Serb broke right back, then repeated the trick two games later to build a 4-1 lead.
Djokovic then saved four break points in the ninth to clinch the second set 6-3.
The writing seemed to be on the wall for Davydenko when he fell behind 3-0 at the start of the third set.
But the Russian staged a remarkable comeback, reeling off four consecutive games to win the third set only to see Djokovic walking off the court.
“I was completely shocked to see him walking out,” Davydenko told reporters.
“He played well for more than two hours as I was making a lot of mistakes,” added the world number four, who committed 60 unforced errors and only converted four of his 18 break-point chances in the two hour 41 minute match.
“I knew he wanted to win in three sets to save his energy. I had no choice but to keep fighting.”
Serbia’s Davis Cup debutant Viktor Troicki, ranked 114th, beat substitute Dmitry Tursunov 7-6 4-6 6-3 in the dead last rubber to make the final score 3-2 as the Russians extended their unbeaten home streak to 15 ties. They last lost at home in the 1995 final against the United States.
“Today is my birthday and I wanted to give myself a small present,” said Troicki, who turned 22 on Sunday. (Editing by Clare Fallon and Alison Wildey)