Ferrero turned in a 6-4, 6-4, 6-4 decision over the German cup rookie in the fifth and deciding match between the teams.
Spain, the defending champion, will play Israel in the semifinals in September. The Israelis gained the semis for the first time by knocking out the Russian team 4-1.
Germany's Philipp Kohlschreiber had tied the duel with Spain at 2-2 by outlasting Fernando Verdasco 6-4, 6-2, 1-6, 2-6, 8-6. Kohlschreiber also got his team's other point by defeating Tommy Robredo Saturday.
Spain won without its top star, world No. 2 Rafael Nadal, who has been sidelined with knee problems.
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