Simona Halep survived a major examination from a rising star to reach the fourth round at the French Open but two-time Wimbledon champion Petra Kvitova is out.
The 10th seed was beaten by the bizarre scoreline of 6-0 6-7 (3/7) 6-0 against 23-year-old Shelby Rogers, who is ranked 108 in the world.
Rogers is through to the last 16 at a grand slam for the first time, and she broke down after clinching the biggest win of her career.
The American, who next plays 25th seed Irina-Camelia Begu, said: "There was a lot of noise and a lot of applause, and a lot of emotions taking over, but I'm one that cries very easily, and I think everyone saw that.
"I immediately started crying, and it was a very incredible moment. It's definitely up there as one of the best moments of my life."
Kvitova has only once made it past the fourth round at Roland Garros, and she said: " I felt like nothing really worked today.
"I think I didn't start the match well and I was feeling very tired and my legs were very heavy. I just felt weird. I didn't really sleep last night. It's definitely one of my worst losses in a grand slam."
Halep reached the final at the French Open two years ago and will fancy her chances of a repeat.
But she was pushed all the way by 18-year-old Naomi Osaka before coming through 4-6 6-2 6-3.
Osaka, who represents Japan but has lived in the US since the age of three, made her breakthrough with a run through qualifying at the Australian Open before losing in the third round to Victoria Azarenka.
She only won two games in that match but showed her rapid development by winning the first set against sixth seed Halep and causing her trouble throughout.
Osaka said: "For sure I think I had opportunities, because I did win the first set. I don't think I really enforced my game on her, and I was making too many unforced errors.
"But she has more experience than me. I feel like I'm not the greatest player ever, so I can't be upset that I lost. I 'm just going to take this as a learning lesson, because it's better than how I played in the Australian Open third round anyway."
Osaka possesses huge power, particularly on her forehand, and she added: " At the risk of sounding really arrogant, I kind of think that I can play with the top-10 players, I feel like I can play with anybody.
"I just have to be consistent and not freak out all the time."
In the fourth round Halep will take on Australian Sam Stosur in a battle of the former runners-up.
Stosur, beaten by Francesca Schiavone in 2010, eliminated last year's beaten finalist Lucie Safarova in a real scrap, finally prevailing 6-3 6-7 (0/7) 7-5.
Fourth seed Garbine Muguruza is looking in good shape to make the quarter-finals for a third straight year after a 6-3 6-0 victory over Yanina Wickmayer.
She could have a real test next, though, against 2009 champion Svetlana Kuznetsova, who is a dark horse and beat Anastasia Pavlyuchenkova 6-1 6-4.
Second seed Agnieszka Radwanska survived an enthralling tussle with Barbora Strycova, winning 6-2 6-7 (6/8) 6-2. During one point both women were sitting on the clay but somehow the rally continued.
In the fourth round Radwanska will take on surprise package Tsvetana Pironkova, who is known for her fine record on grass but blitzed past 19th seed Sloane Stephens 6-2 6-1.
Source: PA
