* Verdasco and Lopez win doubles for crucial third point
* Fourth Davis Cup triumph of the decade for Spain
* First team to win back-to-back titles since Sweden in 1998
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By Kevin Fylan
BARCELONA, Spain, Dec 5 (Reuters) - Spain secured a fourth Davis Cup win and confirmed their status as the team of the decade by extending their lead over Czech Republic to an unassailable 3-0 in Saturday's doubles.
Rafael Nadal's commanding win over Tomas Berdych and David Ferrer's epic comeback against Radek Stepanek had taken Spain to the brink of victory by Friday night and Feliciano Lopez and Fernando Verdasco combined to complete the job.
The two left-handers, heroes of Spain's triumph in last year's final away to Argentina, beat Berdych and Stepanek 7-6 7-5 6-2 for the clinching third point before embracing and sinking to the floor at the Palau Sant Jordi.
The performance underlined the fact that on clay, and in front of a home crowd, Spain are a class apart.
Victory made them the first team to successfully defend the Davis Cup since Sweden in 1998 and it came at the same arena that hosted their first Davis Cup triumph in 2000 against Australia.
That victory was a watershed for Spain, who reached the final again in 2003, this time losing away to the Australians, before racking up further wins against the United States in 2004 and Argentina last year.
"The goal now is just to keep on winning Davis Cups," Verdasco told a news conference. "The more the better."
EAR-SPLITTING
There are four Spanish players in the world's top 20, including Tommy Robredo who was not chosen for the final. That gave captain Albert Costa the luxury of playing Ferrer on the opening day and keeping Verdasco fresh for the doubles.
Czech Republic's relative lack of depth meant they had to go with their leading two for both singles and doubles.
There was not much between the two teams in the first two sets on Saturday, with Spain's greater assurance on the clay surface, plus the ear-splitting support from the 16,200 sell-out crowd, seeing them through the key moments.
Spain took the first set 9-7 on the tiebreak after Berdych had missed a chance to win it on his serve.
The second was decided when Berdych, who struggled for form throughout, let slip 40-0 on his own serve to give Spain the break in game 11, Verdasco sealing the advantage with a crunching forehand from the baseline.
Spain rode the momentum into the third set, breaking in the first game to get the crowd on their feet and raising the decibel level still higher.
"I just have to congratulate Spain," Berdych told a news conference. "They are so strong, at home particularly, and they deserved this." (Editing by Sonia Oxley; To query or comment on this story email sportsfeedback@thomsonreuters.com)