Former French Open champion Jelena Ostapenko of Latvia knocked off No. 2 seed Karolina Pliskova of the Czech Republic in straight sets on Thursday in Paris.

With the 6-4, 6-2 upset in 69 minutes, Ostapenko advanced to the third round at Roland Garros for the first time since winning the trophy in 2017.

Ostapenko registered 27 winners and 19 unforced errors, compared to nine winners and 25 miscues for Pliskova. Ostapenko converted five of her nine break chances.

"I knew it was going to be a tough match, so I was trying to be very focused all match, playing my game, said the 23-year-old Ostapenko, ranked No. 43 in the world. "I tried to keep the ball in play to make sure I'm not missing and making too many unforced errors, but when I had the chance I was going for it."

Her next opponent will be Spain's Paula Badosa, who eliminated 2018 French Open finalist Sloane Stephens 6-4, 4-6, 6-2. Badosa tallied 20 winners but only 18 unforced errors, half the number committed by the 29th-seeded American.

It is the first appearance in the third round at a Grand Slam event for the 22-year-old Badosa, who won the Roland Garros junior singles title in 2015.

"I know (Stephens) has very, very good talent," Badosa said. "But I knew that I had to play my game and to be very intense, and to be there every point. That's what I tried to do, and it went well."

No. 4 seed Sofia Kenin of the United States rallied for a 3-6, 6-3, 6-2 win against Romania's Ana Bogdan. The 2020 Australian Open champion won nine of the last 11 games in the match to avoid the early exit, finishing the match in one hour and 51 minutes.

"The first set just didn't go my way. I couldn't find my rhythm," Kenin said. "She was playing really well. I knew I needed to somehow change my game or else I'm going to be out. Did not want that, definitely."

She will face Romania's Irina Bara, who was leading Alison Van Uytvanck 6-1, 4-0 when the Belgian was forced to retire with an injury.

Other seeded winners on Thursday included No. 8 Aryna Sabalenka of Belarus, No. 7 Petra Kvitova of the Czech Republic, No. 11 Garbine Muguruza of Spain, No. 13 Petra Martic of Croatia and No. 30 Ons Jabeur of Tunisia.