France's Jo-Wilfried Tsonga is emotionally involved in his country's Davis Cup doubles match with Spain on Saturday. France won to stay alive on the weekend. ((Sergio Torres/Associated Press) )

Serbia and France kept won their doubles matches Saturday in Davis Cup to trail 2-1 in their respective semifinals.

Defending champion Serbia is hoping that U.S. Open winner Novak Djokovic will be fit enough to help complete a comeback against Argentina in the reverse singles on Sunday. Rafael Nadal will try to complete a victory for Spain over France.

Spain and Argentina both swept Friday's opening singles matches, but neither came close to winning the doubles.

French duo Jo-Wilfried Tsonga and Michael Llodra routed Feliciano Lopez and Fernando Verdasco 6-1, 6-2, 6-0. Serbia's Nenad Zimonjic and Viktor Troicki beat Juan Ignacio Chela and Juan Monaco 7-6 (4), 6-4, 6-2.

Nadal's mastery on clay means Spain remains the favorite to complete a victory at Cordoba's bullring on Sunday. But Argentina could face bigger problems if Djokovic can play in the first reverse singles match against Juan Martin del Potro.

The top-ranked Djokovic led Serbia to its first Davis Cup title last year after beating France 3-2 in the final, but had to skip Friday's match because of lingering back pain following his win over Nadal in the U.S. Open final on Monday. However, he trained at Belgrade Arena immediately after the doubles victory and is expected to be available.

"If Novak plays, I fancy our chances," Zimonjic said.

Zimonjic and Troicki trailed 1-4 in the second set Saturday, but won eight consecutive games to cruise to victory with two breaks in the third set.

"It was a must-win situation and we played well under the pressure," Zimonjic said.

In the second reverse singles Sunday, U.S. Open quarterfinalist Janko Tipsarevic is expected to face David Nalbandian. Tipsarevic was beaten by Del Potro in the other opening singles on Friday.

"Tomorrow will be difficult two matches, knowing Djokovic will play," Argentina captain Tito Vazquez said.

Spain endured its worst loss in a Davis Cup doubles match, as Tsonga and Llodra needed just 1 hour, 39 minutes to complete their rout.

Tsonga was so pleased with his performance that he immediately lobbied France captain Guy Forget to let him take Gilles Simon's place against Nadal in the reverse singles.

"If he picks me that would be fantastic," Tsonga said, with Forget seated beside him. "I am motivated to go and play if I get picked. If I play I am sure I will certainly play against Rafa in this incredible environment and on the clay. I would really like  that."

Nadal has complained of fatigue after the U.S. Open, but is undefeated in Davis Cup singles matches since losing on his debut in 2004. His 17-1 record includes 13 victories on clay. The six-time French Open champion has lost only five of his last 100 matches on clay.

"Nadal is feeling better, he's training better and I think he'll be in top shape tomorrow," Spain captain Albert Costa said.

"[Tsonga] is one of the best players in the world, very dangerous. But I think Rafa will be even better tomorrow than Friday."

Meanwhile, Roger Federer's Switzerland is on the brink of missing out on a spot in next year's World Group after going down 2-1 against Australia. Lleyton Hewitt and Chris Guccione combined to upset Federer and Stanislas Wawrinka 2-6, 6-4, 6-2, 7-6 (5) in the doubles.

Federer will play teenager Bernard Tomic on Sunday, with Hewitt set to play Wawrinka in the last singles match.

In other playoff matches, Italy and the Czech Republic both secured their spots in the World Group.

The Czechs took an unassailable 3-0 lead over Romania with Tomas Berdych and Radek Stepanek defeating Marius Copil and Horia Tecau 3-6, 6-3, 6-0, 6-2.

Simone Bolelli and Fabio Fognini did the same for Italy, beating Jorge Aguilar and Nicolas Massu of Chile, 6-4, 6-4, 6-4.