Last year's runner-up Simona Halep huffed and puffed past Russian Evgeniya Rodina as the French Open began on Sunday, the Romanian reaching the second round 7-5 6-4.
The third-seed was never really threatened but let her guard down too many times for comfort against a willing opponent on a sun-drenched court Philippe Chatrier.
Halep, the top name in action in the women's draw on day one, broke twice to open a 4-1 lead, only for Rodina to hit back and level at 5-5.
The Russian let another service game slip from her hands with a double fault and Halep clinched the set with a drop shot.
She broke decisively in the ninth game of the second set and wrapped it up with an ace.
"I was a little bit stressed today because it is never easy to start such a tournament," Halep, who lost to Russian Maria Sharapova in last year's final, told a courtside interviewer.
Mirjana Lucic-Baroni (Croatia) beat Lauren Davis (U.S.) 6-3 3-6 6-3
9-Ekaterina Makarova (Russia) beat Louisa Chirico (U.S.) 6-4 6-2
3-Simona Halep (Romania) beat Evgeniya Rodina (Russia) 7-5 6-4
Teliana Pereira (Brazil) beat Fiona Ferro (France) 6-3 6-2