Australian Open champion Sofia Kenin fought off a match point against world number 174 Jacqueline Cristian to reach the quarter-finals of the WTA event in Lyon on Thursday.
Kenin, who had lost her opening matches in both Dubai and Doha in recent weeks, made it consecutive wins in Lyon as she scraped through 6-7 (5/7), 7-5, 6-4.
The fifth-ranked American was on the brink of defeat as Romania's Cristian had match point on her serve at 5-4. Kenin rallied to break her opponent and then forced a third set.
The top seed failed to serve out victory while leading 5-3 in the decider but sealed her place in the next round with a break in the following game.
"Obviously I didn't feel my game that well - I was pretty frustrated the whole match, I couldn't find my rhythm, but I just tried to fight through," Kenin told the WTA website.
"I got the win - it's a relief and I'm happy."
Kenin, 21, will next meet France's Oceane Dodin, who received a walkover against Jil Teichmann of Switzerland.
Second seed Kristina Mladenovic crashed out in the second round after a 6-3, 6-3 loss to Germany's Anna-Lena Friedsam.
Results from the WTA tournament in Lyon on Thursday (x denotes seeded player):
Sofia Kenin (USA x1) bt Jaqueline Cristian (ROM) 6-7 (5/7), 7-5, 6-4
Oceane Dodin (FRA) bt Jil Teichmann (SUI x6) - walkover
Darya Kasatkina (RUS x7) bt Irina Maria Bara (ROM) 6-3, 6-2
Viktoria Kuzmova (SVK x8) bt Tereza Martincova (CZE) 6-4, 4-6, 6-4
Anna-Lena Friedsam (GER) bt Kristina Mladenovic (FRA x2) 6-3, 6-3