Serena Williams, who has been struggling with injury, plays 82nd-ranked Vitalia Diatchenko of Russia.
British number one Johanna Konta – seeded 26th – faces a qualifier, while male counterpart Kyle Edmund meets home hope Jeremy Chardy.
Katie Boulter pulled out of the tournament earlier this month because of a back injury – although there was confusion as her name was still in the draw.
The French Open – the second Grand Slam of the year and the only one on clay – starts on Sunday.
More to follow.