Novak Djokovic begins his bid for a fourth consecutive Grand Slam title on Monday against Poland's Hubert Hurkacz at Roland Garros, while Serena Williams and Rafael Nadal also open their campaigns.
Here, AFP Sport looks at three matches to watch on the second day of the French Open:
Novak Djokovic (SRB x1) v Hubert Hurkacz (POL)
-- First meeting
World number one Djokovic can become only the second man in history to hold all four Grand Slams simultaneously twice if he triumphs in Paris.
The 32-year-old has completely turned his fortunes around since dropping out of the world's top 20 last year following a shock quarter-final loss to Marco Cecchinato. Victory at Wimbledon was his first at a major since 2016, and he has since added two more to move to 15 in total -- behind only Roger Federer and Rafael Nadal on the all-time list.
But Djokovic may not have things all his own way against the 22-year-old Hurkacz on Court Philippe Chatrier. The Pole has had an excellent 2019 so far, rising to 43rd in the rankings after runs to the last 16 in Madrid and the Indian Wells quarter-finals.
Serena Williams (USA x10) v Vitalia Diatchenko (RUS)
-- Williams leads head-to-head 1-0
Williams arrives in Paris still looking for a record-equalling 24th Grand Slam title having failed to lift a major title since returning last year after giving birth to her daughter.
But the American has only played four matches since losing to Karolina Pliskova at the Australian Open, struggling for form and fitness.
All eyes will be on her as she returns to Roland Garros on Monday, having withdrawn from the tournament 12 months ago ahead of a scheduled last-16 clash against old rival Maria Sharapova.
Russian Diatchenko is ranked a lowly 82nd in the world, and retired from her only previous match against Williams at the 2015 US Open while trailing 6-0, 2-0.
Rafael Nadal (ESP x2) v Yannick Hanfmann (GER)
-- First meeting
Nadal starts his tilt at a record-extending 12th Roland Garros title against German qualifier Yannick Hanfmann in the second match on Chatrier.
The 17-time Grand Slam champion comes into the tournament as the second seed, and having beaten old foe Djokovic in the Italian Open final. Nadal holds an incredible 86-2 win-loss record in the French Open, having only lost to Robin Soderling and Djokovic since making his tournament debut in 2005.
World number 184 Hanfmann has come through three rounds of qualifying to set up the once-in-a-lifetime clash in Paris, but thinks being partially deaf could be a slight advantage.
"A centre court full of spectators doesn't affect me," he told German daily Bild in an interview.