Naomi Osaka was fined $15,000 by Grand Slam organisers for boycotting a news conference following her first-round win and the world number two was also warned of possible expulsion from Roland Garros and future majors if she fails to meet her media commitments.
Osaka started her French Open campaign with a 6-4 7-6(4) win over Romanian Patricia Maria Tig but her refusal to honour her media commitments at the claycourt major has caused a stand-off with organisers.
Before the start of the slam, Osaka announced she would not attend any news conferences while in Paris to raise awareness of players' mental well-being, saying the nature of questions from journalists is like "kicking a person when they are down".
Austrian fourth seed Dominic Thiem, a French Open finalist in 2018 and 2019, has struggled for form in recent months and he succumbed to a five-set defeat by Spain's Pablo Andujar.
German Alexander Zverev, who was beaten by Thiem in last year's U.S. Open final, survived a five-set scare against compatriot Oscar Otte while former world number one Angelique Kerber suffered yet another first-round defeat.
Greek fifth seed Stefanos Tsitsipas recovered from a stuttering start to beat France's Jeremy Chardy 7-6(6) 6-3 6-1 to advance into the second round.
Tsitsipas, who won the title in Lyon last week, will next face either American Sebastian Korda or Spain's Pedro Martinez.
German Alexander Zverev recovered from a miserable start to reach the second round with a 3-6 3-6 6-2 6-2 6-0 win against compatriot Oscar Otte.
Zverev has now won all seven of his five-set contests at Roland Garros and will next meet another qualifier, Russian Roman Safiullin.
Belarusian 15th seed Victoria Azarenka beat former champion Svetlana Kuznetsova 6-4 2-6 6-3 to move into the second round.
Azarenka had nine double faults and hit seven fewer winners than Kuznetsova but the Russian was let down by 41 unforced errors in a match where both players converted seven break points.