Former world number one Caroline Wozniacki stayed on course for a Roland Garros showdown with Maria Sharapova on Thursday in a quarter of the draw blown wide open by Serena Williams' shock exit.
Wozniacki, seeded nine this year and a quarter-finalist in 2010, breezed past Jarmila Gajdosova 6-1, 6-4 for a sixth win in six meetings against the Australian.
Gajdosova, now at 72 in the world after playing as a seed in Paris 12 months ago, paid a heavy price for her 40 unforced errors on a chilly Philippe Chatrier court.
Denmark's Wozniacki will next face 23rd seed Kaia Kanepi of Estonia with the prize of a place in the last 16 up for grabs and a huge opportunity to progress further following the elimination of Williams.
The great American's stunning loss to France's Virginie Razzano on Tuesday has removed the most formidable obstacle preventing a quarter-final between Wozniacki and Sharapova.
"I'm happy and healthy," said Wozniacki, who suffered ankle problems in Madrid and breathing difficulties in Rome in the run-up to Roland Garros.
China's defending champion Li Na was also a comfortable winner, breezing past France's Stephanie Foretz Gacon 6-0, 6-2 in just 52 minutes.
The 30-year-old seventh seed has looked impressive in Paris after dropping just three games in her opening round.
"I was nervous at the start, playing a French player here. I saw what happened on Tuesday (Serena Williams' defeat)," said Li.
Fourth seeded Czech Petra Kvitova, a potential quarter-final foe for Li, also coasted into the third round with a 6-1, 6-3 win over Poland's Urszula Radwanska.
Wimbledon champion Kvitova, who only dropped three games in her opening win over Australian teenager Ashleigh Barty, needed 70 minutes to set up a clash with Russia's Nina Bratchikova.
The 22-year-old has twice reached the fourth round in Paris, including last year when she was defeated by Li and she never looked in trouble on Thursday.
She fired 30 winners past the 21-year-old Pole, the younger sister of third seeded Agnieszka Radwanska who had put out Venus Williams on Wednesday.
"She played well, she has good hands and a good touch," said 22-year-old Kvitova of her 79th-ranked opponent.
"But she wasn't very aggressive so I was able to play my game."
The first seed to lose on Thursday was Russian 16th seed Maria Kirilenko who, under the concerned gaze of ice hockey superstar boyfriend Alex Ovechkin, slumped to a 6-4, 3-6, 6-3 loss to the Czech Republic's Klara Zakopalova.
Zakopalova has made the third round for the first time in nine attempts and will face Russian 22nd seed Anastasia Pavlyuchenkova, who put out Melinda Czink of Hungary 4-6, 6-3, 6-3, for a place in the last 16.
Also heading for the exit was former world number one, and three-time semi-finalist, Jelena Jankovkic, the 19th seeded Serb who went down 7-6 (7/4), 4-6, 6-4 to America's Varvara Lepchenko, the world number 63.
"I didn't know her game that well, but there are no excuses. I was 5-2 ahead in the first set and had a set point. I let her come back, it's very frustrating," said Jankovic.
Lepchenko has reached the third round of a Grand Slam for the first time and will face 2010 champion Francesca Schiavone, who beat Bulgaria's Tsvetana Pironkova 2-6, 6-3, 6-1 for a place in the last 16.
Later Thursday, second seed Sharapova, who didn't drop a game in her opening win over Romania's Alexandra Cadantu, takes on Japan's world number 84 Ayumi Morita.
Razzano goes up against Dutchwoman Aranxta Rus who knocked out Kim Clijsters in the second round in 2011.