PARIS  - Spain's Nicolas Almagro and David Ferrer demolished Austria on the opening day of their Davis Cup quarter-final Friday as the five-time champions moved to the verge of the semi-finals.

Almagro took just under two hours to see off Jurgen Melzer 6-2, 6-2, 6-4 in Castellon before world number five David Ferrer, Spain's top player in the absence of Rafael Nadal, needed just 85 minutes to crush Andreas Haider-Maurer 6-1, 6-3, 6-1.

"I'm very happy with my match today, I think I played one of my best matches in Davis Cup," said Almagro, as Spain chase a first win over Austria since 1979.

"The score was easy but the match wasn't. I had to fight for every point and I think I was more focused than him. I beat a great player in a great competition like Davis Cup so I'm very happy."

Ferrer eased past world number 139 Haider-Maurer, who hadn't played a match since a Challenger tournament in February.

The Spaniard was never tested as he took his Davis Cup singles record in Spain to 13-0 as Austria's first Davis Cup quarter-final appearance in 17 years began to turn sour.

Doubles team Marcel Granollers and Marc Lopez can wrap up victory for the defending champions ahead of time if they can see off Austrian counterparts Oliver Marach and Alexander Peya on Saturday.

Victory in the tie would also extend Spain's winning record at home to 23 matches, a run stretching back to 1999 when they lost to Brazil. That defeat was also Spain's last on a clay court in the competition.

The winners of the quarter-final will face either France or the United States in the semi-finals. Those two nations were locked at 1-1 in Monte Carlo after France's Jo-Wilfried Tsonga saw off teenager Ryan Harrison 7-5, 6-2, 2-6, 6-2 before John Isner pulled the 32-time champions level with a 6-3, 6-2, 7-5 win over Gilles Simon.

Isner, the world number 11, had shown his Davis Cup ability in the first round with a shock win over Swiss star Roger Federer which also came on clay. The 2.06m giant hammered down nine aces - as well as eight double faults - as he silenced an enthusiastic home crowd.

"It was a very difficult match," said Simon. "I dropped my serve early and when he gets his nose in front he's really very impressive."

Tsonga overcame a rival ranked 60 places below him but his victory was peppered with 53 unforced errors.

In Prague, 2010 champions Serbia, playing without world number one Novak Djokovic, slipped 1-0 down to the Czech Republic after Tomas Berdych eased past Victor Troicki 6-2, 6-1, 6-2.

The second rubber will be a rematch of the deciding fifth rubber in the 2010 semi-finals when Janko Tipsarevic overcame Radek Stepanek in straight sets. That put Serbia through to the final where they collected their first Davis Cup.

The winners of the quarter-final will face either Argentina or 2005 champions Croatia who were facing off in Buenos Aires.

Argentina, playing in their 11th consecutive quarter-final, were runners-up last year and hold the unwanted record for reaching the most Davis Cup finals without winning the title, having now fallen in four finals.

David Nalbandian begins against Croatian number one Marin Cilic before Juan Martin del Potro takes on fellow giant Ivo Karlovic.

The last time Argentina lost a home tie on clay was against the Slovak Republic in 1998.