Rafa Nadal overpowered France's Jo-Wilfried Tsonga 6-0 6-2 6-4 to give Spain a winning 3-1 lead, and home advantage in the Davis Cup tennis final against Argentina.
Spain will be bidding for a third title in four years when they meet Argentina, who upset the holders Serbia.
Their semi-final in Belgrade was resolved when Novak Djokovic had to retire in the fourth rubber against Juan Martin del Potro with rib and lower back injuries.