Stosur has defeated Belgian Yanina Wickmayer in straight sets (6-2 6-4) to advance to the second round despite a rain-interrupted match.

“I was happy with the match. It was pretty solid, I did what I wanted to do,” Stosur told AAP.

“At Grand Slams, there’s never usually too many straight matches where everything just goes your way and you don’t have to worry about anything.

“There’s those moments where you’ve got to fight through it.”

The 34-year-old is aiming to reach the third round at the Open for a 10th consecutive year and will face No.30-seed Russian Anastasia Pavlyuchenkova.

Fellow Australian Daria Gavrilova had to fight to get the victory over Sorana Cirstea.

The No.24-seeded Australian went down a set but was able to recover for a 4-6 7-6(4) 6-3 win in a two hour, 42-minute.

“I battled the rain, my opponent, the nerves, so it’s pretty nice to get through. I feel a little bit relieved,” Gavrilova said.

“I feel like clay is my best surface and I did put a lot of pressure on myself and I didn’t play great," she added.

Gavrilova matched her previous best result at Roland Garros, which happened in 2015, with her second career win in the main draw, matching second career main draw victory at Roland Garros.

She now meets world No.73 American Bernarda Pera.

Ash Barty showed no signs of a back injury which put her in doubt and took just 64 minutes to defeat Natalia Vikhlyantseva 6-3 6-1.

“It felt really good,” she said.

“I did everything possible with my team to get us in a position to be able to play today,” Barty said.

Isabelle Wallace was making her Grand Slam debut but unfortunately lost to Belgian Alison Van Uytvanck 1-6 0-6 in 52 minutes.