Serena Williams powered her way into the second round of the French Open with a 6-2, 6-3 win over Czech qualifier Andrea Hlavackova.

Williams is gunning for her third major title at Roland Garros and the American encountered few problems in dispatching Hlavackova, who is ranked 166th in the world and has never made it past the first round in Paris.

The 33-year-old was dominant throughout, hitting five aces and 25 winners, while perhaps most importantly there were no visible signs of her troublesome right elbow causing her discomfort.

Four breaks of serve were enough for the world No.1 to seal victory in 59 minutes.

The 19-time grand slam champion will now play German Anna-Lena Friedsam in the next round.

The biggest shock of the day came on Court Suzanne Lenglen, where Canada's Eugenie Bouchard lost 6-4, 6-4 to France's Kristina Mladenovic.

Bouchard, who was seeded sixth, has only won three matches since February and her miserable form continued.

"I honestly don't know what to say," Bouchard said. "It's been kind of the same as how I have been feeling recently on the court. Just not like myself.

"I definitely felt a bit better in Rome. I think that just makes it more disappointing to have a performance like today.

"So I just feel like it's been a while that this has been happening and it's unfortunate but I'm sure one day it will stop."

Fourth seed Petra Kvitova squeezed into the second round after winning 6-4, 3-6, 6-4 against New Zealand's Marina Erakovic.

Kvitova faced the same opponent in the second round at Roland Garros last year and while she won in straight sets on that occasion, the Czech was made to work hard for her victory on Philippe Chatrier.

Losing her serve six times in the match, Kvitova struggled to find her rhythm before edging into round two, where she will now face Spain's Silvia Soler-Espinosa.

"I have to say the conditions weren't really easy for me," Kvitova said. "I think it was quite cold and the balls are really heavy, and they didn't really fly.

"For me it was really difficult to go for the shots. It was tough to make any winners. It was very difficult today. It was quite a long match and a big fight.

"Sometimes I couldn't win my serve so it was a little bit difficult but that's how it is in the first round of grand slams. I'm just glad I'm still in and still playing."

Caroline Wozniacki is also safely through after the fifth seed eased past Italy's Karin Knapp 6-3, 6-0.

Wozniacki has not made it further than the last 16 in Paris since 2010, but she had few problems against Knapp, who arrived in good form having won the Nurnburg Cup on Saturday.

"It was really close in the beginning, there were a lot of deuces and advantages," Wozniacki said. "She obviously is playing really well. She won last week.

"So for me it was a tough first round, but nothing unusual from my other draws this year.

"I was ready for it and just kind of excited - I knew the longer we played the better for me, so I didn't mind at all."