Spain booked their place in the Fed Cup final after beating China 4-1 in their semi-final tie at the Beijing International Tennis Centre.

The European team made sure of advancing when Nuria Llagostera Vives overcame Peng Shuai 6-4 6-4 in the day's first reverse singles to give them an unassailable 3-0 lead in the five-rubber tie after they won both of Saturday's matches.

"We knew we could win the tie but we've never expected to win three matches in a row," Vives said.

Peng said she had a few chances in the second set but that Vives had played better, producing a wider variety of shots and moving around the court faster.

"I felt really sorry. I really didn't want to lose," the world number 68 said.

World number 76 Vives had a controversial line call ruled in her favour in the final game to give her match point and she then forced Peng to return long to seal victory.

"I decided to run a lot and to make her run a lot in order to control the match at my favourite rhythm and used my forehand to put pressure on her," Vives said.

Carla Suarez-Navarro defeated Peng and Vives beat Zheng Jie in Saturday's matches.

China salvaged some pride when twice grand slam doubles champion Zheng, who had come back recently from ankle surgery, overcame Suarez-Navarro 7-6 6-3 in the dead reverse singles rubber.

Spain underlined their dominance in the other dead rubber when Vives and Maria-Jose Martinez Sanchez eased to a 6-2 6-1 victory over Peng and Sun Tiantian in the doubles.

Spain will play holders Russia in September's final after the Russians crushed the United States in Moscow and Spain captain Miguel Margets Lobato was confident about his team's chances.

"We have beaten Italy and today China. I believe we are also strong enough to win the final championship," he said.

Reuters