- Novak Djokovic answers late call to help Serbia to Davis Cup victory over Croatia
- France through to last 16 but Great Britain made to wait
- Reigning champions Switzerland on brink after doubles loss against Belgium
Teammate Viktor Troicki had been due to play in the doubles rubber alongside Nenad Zimonjic, but a draining five-set singles match with Croatian teen starlet Borna Coric on Friday convinced Serbia coach Bogdan Obradovic to draft in the fresher Djokovic.
It was an inspired choice.
The Serbian pair took less than two hours to defeat Franko Skugor and Marin Draganja 6-3, 6-4, 6-1, securing an unassailable 3-0 aggregate lead in the best of five tie after singles wins for Djokovic and Troicki over their Croatian opponents Friday.
"We wanted to finish the job today, to take advantage of the fact that we won the first singles and that was done," Djokovic said in quotes carried by the AFP news agency after the match.
The World No 1. singles player has looked strong all week after losing in straight sets to Roger Federer at the final of the Dubai Tennis Championships seven days ago.
He was cheered on by a packed and passionate home crowd at the Kraljevo Sports Center.
Serbia has won the Davis Cup once before, in 2010 when it defeated Croatia on the way to the final.
France marches on
In the day's other Davis Cup ties, France secured a last 16 slot for the sixth consecutive year. Julien Benneteau and Nicolas Mahut's comfortable doubles victory over Germany's Benjamin Becker and Andre Begemann pushed the French over the line 3-0.
The Bryan brothers fought back to secure doubles victory for the U.S. over Great Britain in Glasgow, reducing the 2-0 deficit built up by singles victories from Andy Murray and James Ward Friday.
Meanwhile, defending champions Switzerland, playing without Roger Federer or Stan Wawrinka, are on the brink after falling 2-1 behind Belgium as Michael Lammer and Adrien Bossel lost 1-6 6-3 6-2 6-2 to Ruben Bemelmans and Adrien Bossel.