Second-seed Karolina Pliskova of the Czech Republic lost in straight sets to world number 31 Petra Martic in the third round of the French Open.
Pliskova, a semi-finalist in 2017, has failed to progress beyond round three in the last two years at Roland Garros.
The 27-year-old had been in good form, beating British number one Johanna Konta to win the Italian Open in Rome earlier this month.
She is the fourth women’s top-10 seed to exit the French Open this year.
Croatian Martic, who last reached the fourth round in 2012, will face two-time quarter-finalist Kaia Kanepi from Estonia or Russian world number 68 Veronika Kudermetova next.
Australian Open semi-finalist Pliskova was broken twice in the first set and three times in the second after she made 28 unforced errors and won only 33% of points on her second serve.
The world number two has yet to win a Grand Slam title but reached the US Open final in 2016.
Top 10 Seeds Out
Karolina Pliskova 2
Kiki Bertens 4
Angelique Kerber 5
Petra Kvitova 6