Reigning Olympic badminton women's singles champion Chen Yufei (CHN) and Rio 2016 gold medallist Carolina Marin (ESP) won their group matches at the Paris Games on Sunday.

Tokyo gold medallist Chen won 21-14 17-21 21-9 against Germany's Yvonne Li, who pushed her opponent hard despite being 34 places below the world number two.

"I was getting used to the court and a bit slow - my competitor was very good," Chen said, adding that she had found the second round problematic.

Marin beat Switzerland's Jenjira Stadelmann 21-11 21-19, bringing her to her knees more than once. Marin, known for being efficient, fierce and vocal, ended the first game in 15 minutes.

"This is how I am. I fight for every point and I show honesty on court," said the Spaniard, who had to pull out of Tokyo after suffering an anterior cruciate ligament injury.

"I don't want to compare this Carolina with that (Rio) one because we're here eight years later. Women's singles has changed a lot and I feel more than ready for this tournament."

Tokyo silver medallist Tai Tzu Ying's (TPE) win over Lianne Tan of Belgium was at times a closer affair, ending 21-15 21-14.

Taiwan's Tai, who came onto the court with both knees in braces, has previously opened up about an issue with her left knee and earlier this year withdrew from the Singapore open.

She told reporters after Sunday's win that she thinks she is still in control but her movements could have been better.

India's PV Sindhu, with two Olympic medals already under her belt - a silver from Rio and bronze in Tokyo - made quick work of Fathimath Abdul Razzaq of the Maldives, winning 21-9 21-6.

The second session kicked off with spectators belting out "La Marseillaise" as French-Bulgarian brothers Christo and Toma Popov warmed up for their men's doubles clash with world number five pair Kang Min-hyuk and Seo Seung-jae.

The hard-fought match ended with the South Koreans winning 21-17 21-15 against the France duo.

China's Liu Shengshu and Tan Ning, the women's doubles world number three pair, eked out a 19-21 21-10 21-16 win after an unexpectedly tough fight with Bulgarian sisters Gabriela and Stefani Stoeva, ranked 22.