Sloane Stephens, runner-up at Roland Garros in 2018, dismantled former world No.1 and No.16 seed Karolina Pliskova 6-0 6-4.
But although everything went smoothly on court for the American on Monday, she said racist abuse of players had got worse.
"Yes, it's obviously been a problem my entire career," said Stephens, who is Black. "It has never stopped. If anything, it's only gotten worse."
She did not go into specific details but said even software such as the one available for players at the French Open, which that is designed to block racist comments, could not stop it.
"I did hear about the software. I have not used it," Stephens, 30, said.
"I have a lot of obviously key words banned on Instagram, but that doesn't stop someone from just typing in an asterisk or typing it in a different way, which obviously software most of the time doesn't catch."
The software provided by organisers for the first time is able to identify and remove racist and other forms of hate speech, and the French Tennis Federation has made it available to all players at the tournament.
Using artificial intelligence, the software filters out abusive comments on social media platforms such as Twitter, Instagram and TikTok.
Stephens said the racism had reached a worrying level.
"When there is FBI investigations going on with what people are saying to you online, it's very serious," she said.
"People online have the free rein to say and do whatever they want behind fake pages, which is obviously very troublesome.
"It's something I have had to deal with my whole career and something I will continue to deal with, I'm sure. That's that."
Former French Open runner-up Anastasia Pavlyuchenkova celebrated her return to Roland Garros with a dominant win over Czech teenager Linda Fruhvirtova, a year after she feared her career might be over.
The 31-year-old enjoyed her best run at a slam at the 2021 tournament before losing to Czech Barbora Krejcikova in the final.
However, she skipped Roland Garros last year, as well as the second half of the season, to nurse a knee injury.
Pavlyuchenkova – three times an Australian Open quarter-finalist – said she was forced to go through extensive rehabilitation and stopped playing tennis completely for five months.
"It was a rollercoaster of emotions because I was sad. I was close to crying, but also sad because I wasn't sure what (comes) after," Pavlyuchenkova told reporters after her 6-2 6-2 victory over the 18-year-old Fruhvirtova.
"There were also thoughts, like 'OK, what if I never come back? What if I never win a match or never be back in good shape? What if that's it?'
"There were a lot of doubts. I barely could jog, walk or sit down. It was painful all the time," said Pavlyuchenkova, who has slipped to No.333 in the rankings.
Two times grand slam champion Petra Kvitova, the 10th seed, fell to a 6-3 6-4 defeat to Italian Elisabetta Cocciaretto, who claimed the biggest win of her career.
Lucky loser from qualifying Elina Avanesyan, of Russia, ranked 134th in the world, also upset a seed, ousting No.12 Belinda Bencic 6-3 2-6 6-4.
Elina Svitolina played – and won – her first grand slam match in nearly 18 months, beating Italy's Martina Trevisan 6-2, 6-2.
Svitolina, 28, and her husband, French star Gael Monfils, welcomed their daughter, Skai, in October.
“Everything is kind of old and new for me right now,” said Svitolina, a former world No.3 but now ranked 192nd.
She hadn't played at a slam since a third-round exit at the Australian Open in January 2022.
with agencies
