GIJON, Spain (AP) - The U.S. reached the end of the road in its Davis Cup run.

The Americans couldn't overcome Spain's superiority on clay, falling to the defending champions when David Ferrer beat John Isner 6-7 (3), 6-3, 6-4, 6-2 Sunday to secure an insurmountable 3-1 lead in their semifinal.

The Americans' strong 2012 run included victories over both Roger Federer-led Switzerland and France away, on clay. But even those impressive victories couldn't propel it past the world's top clay-court nation as Ferrer stayed unbeaten on the surface for his 16th victory.

Three straight road series took a toll on a U.S. team led by Isner now that Andy Roddick has retired and Mardy Fish was absent due to health issues.

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