MADRID — For the third straight time this season, Rafael Nadal won't be fighting for a title on his favourite surface.

Nadal's slump on clay continued on Saturday at the Madrid Open with a third consecutive semifinal elimination, adding to his worst start to the clay-court swing since 2015.

He lost to ninth-ranked Greek Stefanos Tsitsipas, who will try to win his third title of the year in a final against top-ranked Novak Djokovic, who defeated Dominic Thiem 7-6 (2), 7-6 (4) and will have a chance to tie Nadal for the most titles in Master 1000 tournaments with 33.

In the women's final, Kiki Bertens beat two-time Madrid champion Simona Halep 6-4, 6-4.

"It wasn't my best night," Nadal said. "I knew what I had to do, it was clear to me, but I just wasn't capable of doing it. I didn't have a good feeling to do the things I wanted to do and that's it. We don't have to dwell too much on it."

The second-ranked Spaniard, still seeking his first title of the season, had also failed to make it to the final in Monte Carlo and Barcelona, tournaments he had won the last three consecutive seasons. He lost to Fabio Fognini in Monte Carlo and to Thiem in Barcelona. This is the first time since 2004 that Nadal had arrived in Madrid without a title.

"I've won a lot over the years on this surface," he said." But this year it hasn't been the case. I've been really close, but I haven't been able to win."

Nadal, who was yet to lose a set in Madrid this year, had beaten Tsitsipas all three previous times they played, without losing a set, including in the semifinals of the Australian Open.

The 20-year-old Tsitsipas converted on his fourth match point to close out the victory on the Magic Box centre court.

"I'm really happy that I managed to keep my nerves down and fight back. Probably one of the toughest victories I've had in my life," Tsitsipas said. "Adding variety and being unpredictable was the key today."

The young Greek played aggressively from the start, breaking Nadal's serve six times. He saved 11 of the 16 break opportunities he conceded.

"I really liked my fighting spirit," he said. "I went on the court and I was mentally prepared for a fight."

Tsitsipas will be playing in his fourth final of the season and will have a chance to become the first player to win three titles this year, adding to his triumphs in Estoril and Marseille. He is the tour's winningest player in 2019 with 27 wins.

"I have to be mentally prepared for a tough match," said Tsitsipas, who defeated Djokovic in Toronto last year. "He's in a pretty good state of his tennis, so it won't be easy."

DJOKOVIC ON TOP

Djokovic can add to his Australian Open title on Sunday thanks to his confidence-boosting win over an in-form Thiem.

"Dominic is one of the best tennis players in the world at this moment, especially on this surface, so this was a very big win for me," Djokovic said.

The fifth-seeded Thiem, who beat Roger Federer in the quarterfinals, had won two straight against Djokovic and was trying to make his third straight Madrid final following losses to Rafael Nadal in 2017 and Alexander Zverev in 2018. The Austrian was also attempting to become the first player to win three titles this season, adding to triumphs in Indian Wells and Barcelona.

"I thought he was the favourite coming into this match because of his win in Barcelona and the way he played winning against Roger yesterday," said Djokovic, who will be trying to add to his Madrid titles from 2011 and 2016.

"I was still kind of trying to find my best game on clay," Djokovic said. "These are exactly the matches that I need. I'm very, very pleased with this win."

Thiem played well in both sets but Djokovic prevailed in both tiebreakers.

"I think that to beat these players, Novak, or Rafa, you need to have this little luck, this momentum going for you, and that was not the case today," Thiem said. "Some break points for me were a little bit unlucky and some of them I missed, which I usually don't do."

BERTENS WINS

Last year's runner-up Bertens defeated Halep for her second title of the year, adding to her victory in St. Petersburg, Russia.

"I am really proud of this week. I played some good tennis," said Bertens, who next week will reach a career-high No. 4 ranking.

The seventh-ranked Dutch became the first woman to win the Madrid title without dropping a set. She had victories over three Grand Slam champions in the Spanish capital — Jelena Ostapenko, Sloane Stephens and Petra Kvitova. Bertens lost to Kvitova in last year's final.

Halep, winner in Madrid in 2016 and 2017, lost the chance to take over the No. 1 ranking from Naomi Osaka.

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