Rafael Nadal rallied past David Ferrer 4-6, 7-6 (3), 6-0 Friday in the quarterfinals of the Madrid Open, maintaining his bid to reach a seventh straight final since returning from a knee injury.
Top-ranked Serena Williams struggled before defeating Anabel Medina Garrigues 6-3, 0-6, 7-5, and second-ranked Maria Sharapova joined her in the semifinals after easing by Kaia Kanepi of Estonia 6-2, 6-4.
In a meeting of Spain's top-ranked players, Ferrer's baseline game on the red clay almost proved too much for Nadal.
But Nadal won the tiebreaker to force a third set and won six straight games to improve his career record against Ferrer to 18-4, avoiding an early exit with Novak Djokovic and Roger Federer this week.
"I'm just happy to be back in the semifinals at Madrid," said Nadal, who won in 2005 and 2010.
Nadal will play either Pablo Andujar or Kei Nishikori, who upset Roger Federer on Thursday.
The Spaniard has won four titles this year since sitting out seven months with tendinitis in his left knee.
The fourth-seeded Ferrer's ability to keep points alive with error-free long rallies gave him an early lead. He used his speed to break twice in the second set, sealing both with approach shots at the net for a 4-2 advantage.
Nadal then dug in and broke twice to win the next three games.
Ferrer had an opportunity to earn two match points when leading 5-4 and 30-15. He had plenty of time to slam a floating ball into an open court but instead fired at his opponent's feet, allowing Nadal to scoop it over the net.
"It was a tightly contested match," Nadal said. "David deserved it more than I did to reach the semifinals, but that is sport. I was lucky to somehow save that ball down 15-30.
"After missing his chance, David fell apart a little. He lowered his intensity in the third set and I didn't have to do as much."
Nadal was steadier in his shot-making in the tiebreaker, and he only got better in the third set. After placing a perfect lob near the baselines, he wowed the Caja Magica crowd by nailing a forehand winner while almost stumbling to the ground en route to building an insurmountable 4-0 lead.
Sharapova will play Ana Ivanovic after the Serb dispatched Angelique Kerber 6-3, 6-1.
Defending champion Williams will face Sara Errani, who downed Ekaterina Makarova 6-4, 6-3.
Williams appeared to be worn down after being blanked in the second set and falling behind 4-2 in the third. But she rallied to break the Spaniard's serve twice.
"I just wasn't really into it, my feet weren't moving," Williams said of the second set. "To change it I got up early (before the third set) and did some high knees, some stretching, anything I could to get my intensity back up to where it needs to be."