Naomi Osaka has crashed out of the Madrid Open in the second round, leaving her French Open hopes in disarray.
The World No.2 was knocked out of the clay-court event by Karolina Muchova 6-4 3-6 6-1 on Sunday, ending any prospect of a clash with Ash Barty in the final.
Muchova, a semi-finalist at the Australian Open which ended up being won by Osaka in February, powered through the deciding set with surprising ease to cause the shock of the championship.
"It was a tough match today, but we had some preparation," Muchova said.
"I was ready to play with all I had today, and to use all the weapons I could and (do) what I can."
Osaka, who was coming off a quarter-final loss to Maria Sakkari in Miami, shrugged: "In the third set, I felt I just started off really bad and I couldn't afford to do that."
Osaka, the reigning US and Australian Open champion, has seven career hard-court titles but has never managed to lift a clay-court trophy.
Playing her first clay-court event since the 2019 French Open, Osaka beat compatriot Misaki Doi in the first round but came unstuck against Muchova.
"I have a pretty positive outlook on it," said Osaka after the match.
"I can control my attitude and how hard I fought and for me, I thought I did that really well.
"Physically I don't think I got tired. I just made some pretty bad decisions point-wise in really crucial moments.
"So I think I'll learn from that, and hopefully - I don't really want to play her on clay anymore - but maybe next time we play, I'll make better decisions.
"I'm really happy with how I was able to talk with my team after I lost and after I came off the court. I think we really have a plan now, so I think it's good."
Tennis world in disbelief over Naomi Osaka shocker
Osaka is bidding to win a third consecutive major title at the French Open next month but has never previously made it past the third round in Paris.
"These tournaments are called warm-up tournaments and of course we all come here to win and do well at these tournaments too, but I would prefer to peak at the French as opposed to winning this tournament and then kind of going downhill," Osaka said.
Muchova next faces 16th-seeded Sakkari, who defeated Anett Kontaveit 6-3 6-1.
Elsewhere, two-time Madrid champion Simona Halep held off a late fightback from China's Zheng Saisai to win 6-0, 6-4.
However Victoria Azarenka is out after she withdrew from her second round match against Jessica Pegula with a back injury.
Anastasia Pavlyuchenkova beat sixth-seeded Karolina Pliskova 6-0 7-5, while No.5 seed Aryna Sabalenka defeated Daria Kasatkina 6-3 6-3.
Barty, the top seed who is chasing her fourth title of the year, will be in action again in Monday's last-16 clash when she faces Iga Swiatek, her successor as the French Open champion.
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