Thiem upsets Federer to reach Madrid semifinals

Fifth-seeded Dominic Thiem saved two match points en route to stunning fourth-seeded Roger Federer 3-6, 7-6 (11), 6-4 on Friday to reach the semifinals of the Mutua Madrid Open.

Thiem staved off the match points in the second set tiebreaker and then outplayed the Swiss star in the third.

"The match was so close," Thiem told reporters afterward. "I was really lucky to save the match points.

"Roger was playing unbelievable on the clay. I'm very, very happy to win. He is so special, maybe the best ever in tennis, he has something different. Every time you play him, every point is a big challenge."

The Austrian will next face top-seeded Novak Djokovic, who advanced without playing as ninth-seeded Croatian Marin Cilic withdrew due to a stomach virus.

Federer was playing on clay for the first time since Rome in May of 2016. Coincidentally, he lost to Thiem in his final match of that tournament too.

"I feel very good about my game," Federer said afterward. "I thought I had some good matches here. I feel good on the clay right now."

Thiem had eight aces in a match that took two hours and 11 minutes.

Second-seeded Rafael Nadal and eighth-seeded Stefanos Tsitsipas will meet in the other semifinal.

Nadal sailed to a 6-1, 6-2 win over Switzerland's Stan Wawrinka, while Tsitsipas outlasted third-seeded German Alexander Zverev 7-5, 3-6, 6-2.

Nadal, who is two victories away from his sixth Madrid title, dispatched Wawrinka in just 68 minutes while winning in front of the home country's fans.

"It was a very positive match. I'm very happy with the way that I played and in general terms, it was a great performance," Nadal said after the match. "I'm happy, it was an important moment for me and I'm really happy to be through this way."

Nadal hasn't dropped a set in three previous matches against Tsitsipas but he is expecting a battle from the Greek in the semis.

"He's playing well. He won last week in Estoril and he's already won a lot of good matches this week," Nadal said. "He comes to that semifinal with plenty of confidence. It's going to be a tough one, I hope to be ready for it. I'll need to play my best. Today was a good example. I need to continue tomorrow, that's the goal."

Tsitsipas eliminated defending champions Zverev in two hours, 10 minutes to earn another shot at Nadal.

"I'm really happy and satisfied with my performance," Tsitsipas said afterward. "I think I deserved the match at the end. I was playing really well, feeling really comfortable on the court. When you feel like this, you can do miracles."

--Field Level Media