Mardy Fish has vowed to make Andy Roddick proud as the USA aim for a first Davis Cup victory over Croatia.

Roddick pulled out of the Porec clash, which begins tomorrow, with a hip injury sustained in his heartbreaking five-set defeat by Roger Federer in the Wimbledon final last weekend.

The world number six has played in all his country's last 18 ties and Fish is eager to make his mark as the US look to avenge first-round defeats by Croatia in 2003 and 2005.

"I'm honoured to be selected to represent the United States in Davis Cup again and am excited to join the team in Croatia," said Fish.

"Obviously Andy had a very difficult match on Sunday in the Wimbledon final and I know this was a very hard decision for him to make. I hope I can help make him proud this weekend."

Fish will play the second singles match tomorrow against Croatian number one Marin Cilic while Blake opens proceedings against 6ft 10in Ivo Karlovic on the indoor clay.

World number one doubles team Bob and Mike Bryan will take on Wimbledon quarter-finalist Karlovic and Lovro Zovko on Saturday.

Defending champions Spain are also without their biggest star as world number two Rafael Nadal continues his recovery from knee problems.

David Ferrer has also pulled out of the quarter-final rematch against Germany with a hamstring injury but the team is still strong, with top-10 star Fernando Verdasco supported by Tommy Robredo, Feliciano Lopez and Juan Carlos Ferrero.

Verdasco is likely to prove a formidable first opponent for debutant Andreas Beck in Marbella while Robredo has been given the second singles berth and will face German number one Philipp Kohlschreiber.

Lopez and Verdasco are scheduled to play doubles against Nicolas Kiefer and Mischa Zverev, which means no place for Ferrero, who has not played Davis Cup since 2005 but rolled back the years by reaching the Wimbledon quarter-finals.

Argentina, who have been runners-up twice in the last three years, will rely heavily on world number five Juan Martin Del Potro in their tie against the Czech Republic in Ostrava.

Del Potro will take on Ivo Minar in the second match tomorrow after Czech number one Tomas Berdych, another impressive Wimbledon performer, has faced Juan Monaco.

Del Potro is then set to play doubles with newcomer Leonardo Mayer against a strong-looking Czech team in French Open champion Lukas Dlouhy and Radek Stepanek.

Stepanek would have been expected to play singles as well but he has been struggling with a knee injury.

The remaining last-eight encounter sees outsiders Israel take on Russia in Tel Aviv.

The visitors are missing Nikolay Davydenko and Dmitry Tursunov but should still have few problems reaching the semi-finals.

In tomorrow's singles matches, Harel Levy and Dudi Sela face Igor Andreev and Mikhail Youzhny respectively while Israel will have high hopes for doubles pair Jonathan Erlich and Andy Ram against Igor Kunitsyn and Marat Safin.