There were differing fortunes for two former French Open champions in Paris on Saturday.
Svetlana Kuznetsova knocked out fifth seed Petra Kvitova to reach the fourth round but Ana Ivanovic was beaten by Lucie Safarova.
Ivanovic has been having her best season since winning the title in Paris in 2008 but had lost her previous four matches against left-hander Safarova.
It was the same story on Saturday as the Czech won 6-3 6-3 to reach the fourth round at a grand slam for the first time in seven years.
Ivanovic had been seen as one of the favourites to reach the final from the bottom half of the draw and she was hugely disappointed with her performance.
She said: "My clay-court season was really good. I was very happy about that.
"Everyone was talking about seeds coming out, but not in my part (of the draw). I had a really tough opponent today. I lost to her a lot of times before. So I knew she was going to be dangerous opponent.
"I'm very disappointed about my loss today. It's hard to tell what can happen but definitely this loss is tough."
Safarova, who held match point against eventual Australian Open champion Li Na in the third round in Melbourne in January, next plays 2009 Paris champion Kuznetsova.
Kuznetsova and Kvitova was a meeting of two former grand slam champions and it took three hours and 13 minutes to separate them, the Russian winning 6-7 (3/7) 6-1 9-7.
After winning the opening set on a tie-break, Kvitova was hampered by a right thigh problem for which she twice received treatment off court.
The Czech produced some excellent tennis, particularly when she was behind in the decider, but she will feel this was an opportunity missed after twice serving for the match.
Kuznetsova gave Serena Williams a fright in the quarter-finals last year and is always a dangerous player on clay.
The 27th seed said: "I knew I was going to go out there, and I was going to give everything I could and run every mile, every metre I could, and put as many balls back, try to be aggressive.
"Petra was inside the court and I was next to the fans. But I just tried my best. I was very strong mentally and I'm really happy with that.
"I feel really good. I feel really excited, happy. I really feel almost like Rafa out there."
Fourth seed Simona Halep continued her swift progress through the draw with a 6-3 6-0 victory over Maria-Teresa Torro-Flor.
The Romanian is the only one of the top five seeds still in and the second favourite for the title behind Maria Sharapova despite only having reached one grand slam quarter-final.
The 22-year-old should face her first real test in the next round against 15th seed Sloane Stephens, who is once again showing her best form in the grand slams.
Stephens is through to the second week at a sixth consecutive grand slam after defeating big-hitting Russian Ekaterina Makarova 6-3 6-4.
Stephens and Halep have met three times before, with the American having won the last two.
Halep, who is reading Harry Potter to help improve her English, did not expect to be the highest seed left at this stage of the tournament.
She said: "The first three seeds, they lost. That's a surprise for everyone.
"It's not easy to be the first seeded now in the tournament. But I try just to keep out from me the pressure and just to play every match.
"I played against (Stephens) in Australia a few years ago and she beat me very fast. Now I think I'm more prepared than that moment."
Sixth seed Jelena Jankovic will meet 10th seed Sara Errani after both raced through their third-round matches.
Jankovic defeated Romania's Sorana Cirstea 6-1 6-2 while Errani, the runner-up in 2012, dropped just one game against Israel's Julia Glushko.