Of the eight top-25 seeds in action before Pegula, seven moved into the second round in straight sets, much to their relief on another sweltering day in the French capital.
Top seed Aryna Sabalenka and fourth seed Coco Gauff led the way, followed by Victoria Mboko (No.9), Naomi Osaka (16), Iva Jovic (17), Madison Keys (19) and Anna Kalinskaya (22).
The exception was Linda Noskova, the 12th-seeded Czech. However, since her 7-5 7-6 (7-3) conqueror was Maria Sakkari, former world No.3 and a 2021 French Open semi-finalist, it wasn't that big a shock.
The lack of drama meant much of the attention was on what players wore.
Sabalenka looked light on her feet on Court Philippe-Chatrier, despite wearing two thick diamond necklaces in a 6-4 6-2 win over Jessica Bouzas Maneiro.
"Diamonds, I don't really feel the heaviness, but I can imagine how it looks from the outside," said Sabalenka, runner-up last year to Gauff. "So I feel pretty comfortable. For me, it's important to look good."
The four-time major winner was initially going to wear three necklaces, but said she thought that might be too much.
"It probably sounds a bit crazy, but when I feel good about what I'm wearing, how I look on court, I tend to perform much better," Sabalenka said.
"I like to bring a little bit of fashion on the tennis court. I know the dress that I will wear on the grand slam, and I just try to come up with something to match the outfit."
Meanwhile, Osaka walked on to Court Suzanne Lenglen in a black Kevin Germanier skirt, before unveiling a layered yellow-brown and gold Nike match dress.
Such was its sparkle she packed a couple of low-key back-up dresses in case she was banned from wearing it.
"When I first saw the match dress in real life, I felt I look like the Eiffel Tower at night, when it's bright," Osaka said after her 6-3 7-6 (7-3) win over Germany's Laura Siegemund.
"I actually got a little worried, because when the sun hits the dress, it reflects a lot. So I was a little scared that the umpire was going to kick me off the court."
Gauff's biggest problems came in simply getting on court to play fellow American Taylor Townsend.
"We got in a mini car accident on my way," she revealed. "We ran into a (pole). I spilled my juice all over the car.
"The car was not drivable, so we ended up taking a taxi. Then right before I went on to court, my dress got stuck, so my physio was in the bathroom trying to help me take it off. It was an eventful day."
Perhaps inevitably she began slowly, though she also attributed that to nerves, She was a point away from slipping two breaks of serve behind, before easing to a 6-4 6-0 victory.
"I have so many great memories on this court," Gauff said. "I was a little nervous going out today, that showed a bit, but I was able to find my calm."
Canadian Mboko cruised past Nikola Bartunkova 6-1 6-2 on her Roland Garros debut. The 19-year-old will next face another Czech player, Katerina Siniakova.
with agencies
