Leander Paes and Radek Stepanek fought hard but lost 6-4, 7-6(5) to David Marrero and Fernando Verdasco in a Group B match at the ATP World Tour finals on Wednesday.

Now the seventh seeds must beat Marcel Granollers and Mark Lopez in their last Group match to ensure progress to the last four without depending on the other teams’ performance. Paes and Stepanek had beaten Alexander Peya and Bruno Soares on Tuesday.

Marrero and Verdasco became the first team to qualify for the semifinals with two wins from as many matches.

The Spaniards stayed solid from the baseline and at the net. They broke Stepanek for a 5-4 lead in the first set, and Verdasco held at love, clinching the set with an ace. The pair had lost just two points on serve in the entire set.

Paes was broken in the opening game of the second set, but the seventh seeds broke back and led 3-2. There were no further breaks, and in the tie-break Verdasco hit a double fault on the first matchpoint at 6-4, his second serve hitting Marrero on the shoulder.

However, Marrero hit a winner the second matchpoint to close it out.

On Tuesday, Roger Federer showed flashes of his best but Novak Djokovic exposed the Swiss maestro’s fading powers with a three-set victory.

Djokovic briefly looked in trouble midway through an absorbing Group B match but eventually surged to a 6-4, 6-7(2), 6-2 win.

Djokovic’s win, his 18th in a row since losing to Rafael Nadal in the US Open final, was his second in four days over Federer and kept alive his slender hopes of toppling the Spaniard from the top of the world rankings. Djokovic was made to work hard against old adversary Federer.

“It’s slow here and it’s the first match, so there’s going to be errors,” Federer, who had not lost his opening match at the Tour Finals since 2008, told reporters.

Federer, who has won a record six titles at the year-ender, remained hopeful of beating Richard Gasquet on Thursday to keep alive his hopes of ending a disappointing year on a high.

Djokovic will face Juan Martin del Potro on Thursday and said he was relieved to survive a tough opener. “It was probably the toughest start I could get for this tournament, especially considering the scheduling that I had, playing two days ago in Paris finals,” he said.

The results:

Singles: Group B: Novak Djokovic bt Roger Federer 6-4, 6-7(2), 6-2.

Doubles: Group B: David Marrero & Fernando Verdasco bt Leander Paes & Radek Stepanek 6-4, 7-6(5). Group A: Ivan Dodig & Marcelo Melo bt Bob Bryan & Mike Bryan 3-6, 6-3, 10-8.

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