Five-time champions Spain reached the Fed Cup final Sunday, thumping China 4-1 to set up a title decider with Russia.
Nuria Llagostera Vives beat Peng Shuai 6-4, 6-4 in one hour and 34 minutes to give Spain an unassailable 3-0 lead after the first match.
"We knew we could win but we never expected to finish the first day 2-0 up and to be 3-0 up on the second day but we worked for this all week," Llagostera said.
"We have been very focused and we knew what we had to do to win every match," she added, saying team spirit was one of the reasons for the victory.
Team captain Miguel Margets Lobato said he believed the Spanish were capable of going on to lift the Fed Cup, even against tennis powerhouse Russia, who romped to a decisive 3-0 lead over the United States in Moscow.
"No matter what our former glories are, we are putting in a lot of effort now and we don't give up. We will not be afraid of the Russian team. We play with passion and will have a chance to win."
Spain did not lose a single set in the first three matches of their semi-final clash.
In the first match on Sunday, Llagostera, ranked 76, was in the groove quickly, putting pressure on Peng's serve in the opening game and breaking in game three for an early advantage.
The single break was all the Spanish player needed to take the first set 6-4 in 43 minutes.
Llagostera broke again in the third game of the second set but Peng, buoyed by the passionate crowd, broke back straight away to level at 2-2, forcing the dominant Spaniard on to the defensive.
But Llagostera, who mixed crunching backhands with some delicate touches, including an exquisite lob, continued to play the big points well and broke again to take a 4-3 lead, going on to take the set 6-4.
Peng, ranked 68, battled hard but could not gain a foothold in the match, with unforced errors proving costly against her more consistent opponent.
"I think I played better today than yesterday. If I'd played as well yesterday, I might have won," said Peng.
"(Llagostera) played well today and runs so fast. I had some chances in the second set but I did not take them."
In the final singles match of the tie, Zheng Zie pulled one back for China, beating Carla Suarez Navarro 7-6 (7-5), 6-3.
But in the doubles clash Llagostera and Maria Jose Martinez Sanchez thrashed the Chinese pairing of Peng and Olympic doubles gold medallist Sun Tiantian 6-2, 6-1.
Spain led 2-0 overnight after two straight-sets wins here Saturday after Llagostera beat Zheng 6-3, 6-4 and Suarez overcame Peng 6-3, 7-6 (7-4).
China, making their first ever semi-final appearance, were unable to make the most of the advantage of playing on the fast hard courts of the indoor International Tennis Centre against a Spanish side who prefer clay.
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