Iga Swiatek was given a bouquet of flowers on court for her birthday
Defending champion Iga Swiatek celebrated her 20th birthday with victory over Slovenia's Kaja Juvan in the French Open first round.
The Polish eighth seed beat her best friend on the tour 6-0 7-5.
"She didn't give me any birthday gifts so I'm really happy I could win those important points," Swiatek said.
American 23-time major champion Serena Williams started her campaign with a hard-fought 7-6 (8-6) 6-2 win against Romania's Irina-Camelia Begu.
In the first official night session at Roland Garros, 39-year-old Williams was far from her best but found a way through against world number 74 Begu.
Williams, who is again trying to equal Margaret Court's all-time record of major wins, squandered a 5-2 lead in the first set and had to fight off two set points in the tie-break.
The emotion of pulling through to win the opener was evident from the huge roar from Williams, which echoed around a near-empty Court Philippe Chatrier – closed to the French public because of the coronavirus curfew imposed at 21:00 local time.
That enabled the three-time French Open champion to settle down in the second set, breaking Begu's serve in the opening game and again in the seventh on her way to victory.
Williams' trainers have the phrase 'Je ne m'arrêterai jamais' – translated as 'I will never stop' – printed on them for the tournament
'I prepared notes before speaking with Nadal'
While she did not receive a gift from Juvan, Swiatek did get one early birthday present – the chance to hit with her idol Rafael Nadal.
After her opening match, the reigning Roland Garros champion confessed she had to pre-plan some conversations with the 13-time men's singles champion for during the practice session .
"I had to prepare – write some small topics not to have awkward silence," said Swiatek, who has a T-shirt signed by the 20-time Grand Slam champion on her bedroom wall at home.
"Even though I am pretty introverted, it was really fun for me.
"I got to feel his forehand and his topspin. It gave me a lot of positive energy.
"It was really a huge inspiration for me."
Kenin wins battle of Grand Slam champions but Andreescu & Muguruza are out
Sofia Kenin won the battle of the Slam champions beating Jelena Ostapenko
In a battle of Grand Slam champions, 2019 Australian Open winner Sofia Kenin, 22, overcame stiff resistance from 2017 French Open champion Jelena Ostapenko to win 6-4 4-6 6-3.
American Kenin, who was runner-up to Swiatek in last year's Roland Garros final, will face qualifier and compatriot Hailey Baptiste for a place in the third round
But there was disappointment for Canadian sixth seed Bianca Andreescu,the 2019 US Open champion, who lost 6-7 (1-7) 7-6 (7-2) 9-7 to world number 85 Tamara Zidansek of Slovenia.
Spain's 12th seed Garbine Muguruza lost 6-1 6-4 to 18-year-old Ukrainian Marta Kostyuk.
The 2016 champion has struggled with injury during the clay-court season, and called the trainer during the match.
Meanwhile, Dutch 16th seed Kiki Bertens was beaten 6-1 3-6 6-4 by Slovenia's Polona Hercog, but there were wins for Belgium's 14th seed Elise Mertens and Swiss 10th seed Belinda Bencic.
Bencic beat last year's semi-finalist Nadia Podoroska of Argentina 6-0 6-3.
There will be no more British women's interest in the singles after Johanna Konta and Heather Watson lost their first-round matches.
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