After clinching the weekend win Saturday when Marcel Granollers and Marc Lopez bested a Kazakhstani doubles tandem of Korolev and Yuri Schukin, Spain also won a pair of dead rubbers Sunday.
Nicolas Almagro dispatched Evgeny Korolev 6-3, 6-4 in one match and Granollers slipped by Andrey Golubev 6-3, 6-7 (2-7), 6-3 in the other at Oviedo.
The Spaniards, playing this year without star Rafael Nadal, have won five of the last 12 Davis Cup championships.
They now move on to host Austria in April's semifinals.
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