British number one Johanna Konta earned her first victory in the French Open main draw with a straight-set win over Germany's Antonia Lottner.
Konta, seeded 26th, won 6-4 6-4 against the world number 147.
A scrappy first set with seven breaks of serve ended up going in Konta's favour.
Both players settled down in the second, Konta earning the only break in what proved to be the match-winning game.
Konta took her first match point when Lottner could not return a thumping backhand, setting up a second-round match against American wildcard Lauren Davis.
The former Wimbledon semi-finalist is the first Briton through at Roland Garros, with men's number one Kyle Edmund meeting France's Jeremy Chardy later on Monday.