Belgian Clijsters lost the first set
Australian Open champion Kim Clijsters fought back from a set down to beat Kristina Barrois 4-6 6-2 6-0 and reach the last eight at the Paris Open.
German Barrois led 2-1 on breaks of serve to take the first set but was then broken three times in the second as Clijsters began to exert pressure.
The top seed won the last nine games of the match as her class shone through.
If Clijsters reaches the semi-final she will take the WTA number one spot from Caroline Wozniacki.
The 27-year-old Belgian, who could now play fifth seed Nadia Petrova, said she was concerned after losing the opening set.
"It's been a busy last few weeks. I was playing at a different place and I also had never played her before. I was getting used to it all," said Clijsters.
"Even when I lost the first set I wasn't worried. I got it together in the second set and put pressure on her serve. That was good enough."
Meanwhile, sixth seed Andrea Petkovic of Germany faced 17 break points in her match against compatriot Angelique Kerber but still came away with a 7-5 3-6 6-2 victory in the first round.
Seventh seed Yanina Wickmayer saved a break point at 4-2 down in the first set before going on to record a 7-6 [7-1] 6-2 win over Russia's Elena Vesnina.