Madrid: Ashleigh Barty's first clay-court quarter-final has ended in defeat as former world No.1 Simona Halep ended the Australian's 11-match winning streak with a clinical victory at the Madrid Open.
The Romanian kept her hopes of regaining the world No.1 ranking alive with an efficient 7-5, 7-5 win, although an occasionally off-balance Barty battled gamely before losing to a top-five player for the first time this year.
She twice broke back to level sets on Thursday when Halep seemed on track for an easier progression to the semi-finals.
However, the world No.3 was never seriously threatened as Barty, who beat Halep on Sydney's hard courts in January, committed 37 unforced errors.
The world's premier clay-court player also relied on an accurate first serve (87 per cent) to condemn Barty to her first defeat since Indian Wells and dash hopes of back-to-back semi-final appearances after her Miami Open triumph last month.
Barty will still rise to at least No.8 in the world rankings this week despite the setback to her French Open preparations.
Halep now faces unseeded Swiss Belinda Bencic, who beat world No.1 Naomi Osaka, a result that means Halep, the reigning French Open champion, can retake top spot by winning her third Madrid title.
Reaching the last four would have secured Osaka's grasp on top spot for another week but she lost 3-6, 6-2, 7-5 to the resurgent Bencic.
Osaka has limited experience on clay but looked poised for a fine win when she served for the match at 5-4 in the decider only for Bencic to reel off three games in a row and book a clash with Halep.
Barty's third-round defeat of Yulia Putintseva had improved the 23-year-old Queenslander's win-loss record in 2019 to 23-3, matching Lleyton Hewitt's remarkable start to 2003.
Meanwhile, Novak Djokovic booked his place in the quarter-finals of the men's event with a 6-1, 7-6 (7-2) win over Jeremy Chardy.
The Serbian world No.1 made light work of his French opponent on the clay in the first set but struggled in the second.
Djokovic saved set point at 4-5 with a fine serve, preserving his record of never having dropped a set against Chardy in 13 matches, going on to seal the tie-breaker with a forehand winner.
"I was set point down, it could have gone a different way," said Djokovic, who won in Madrid in 2011 and 2016.
"I wasn't really thinking about my score against him in that moment, I just wanted to play it well.
"The wind picked up in the second set so it was faster and you had to just pick a position sometimes and kind of rely on your instinct, and it worked well."
Djokovic will next face Marin Cilic on Friday, after the Croatian beat Laslo Djere 4-6, 6-3, 6-2.
Dominic Thiem also progressed with a 6-4, 7-5 win over Italian Fabio Fognini.
Austrian Thiem now faces Roger Federer, who survived two match points against French maverick Gael Monfils to extend his clay-court comeback.
The evergreen 37-year-old did not drop a game in a dominant first set but was dragged into an intense battle by an inspired Monfils before prevailing 6-0, 4-6, 7-6 (7-3).
World No.3 Federer, playing his first tournament on clay for three years as he prepares for the French Open, said: "I think Gael did a nice job of not being frustrated losing the first set.
"I lost five games in a row and it didn't look good for a while but I hung in. There were some highly stressful moments but I mixed it up nicely."
Federer's fellow Swiss Stan Wawrinka, champion at Roland Garros in 2015, continued to produce some vintage form as he beat Japan's Kei Nishikori 6-3, 7-6 (7-3).