Paris - Title challengers Marin Cilic and Dominic Thiem struggled into the French Open last 32 on Thursday as Serena Williams, Maria Sharapova and Rafael Nadal waited to join them.
Third seed Cilic reached the third round for the eighth time with a 6-2, 6-2, 6-7 3/7), 7-5 win over Polish qualifier and world No 188 Hubert Hurkacz.
Former US Open champion Cilic, who reached the quarter-finals in Paris last year, will face Steve Johnson of the United States for a place in the last 16.
However, it was a roller-coaster of a performance by newly-wed Cilic who cracked 48 winners but also 52 unforced errors.
"I was in control but played a poor third set so I had to start all over again," said 29-year-year-old Cilic.
"I had to be positive, positive, positive. I screamed just to let it all out and I got the break in the 11th game."
Seventh seeded Thiem, a semi-finalist in 2016 and 2017, racked up his 31st win of the year.
The Austrian, the only man to beat world No 1 Rafael Nadal on clay this year, saw off Greek teenager Stefanos Tsitsipas 6-2, 2-6, 6-4, 6-4 in a match which had been suspended overnight after the third set.
Next up for Thiem is Italy's Matteo Berrettini.
Highly-rated Canadian teenager Denis Shapovalov was knocked out by Germany's Maximilian Marterer 5-7, 7-6 (7/4), 7-5, 6-4.
World number 70 Marterer, 22, has now reached the third round at successive Grand Slam events and will face a lucky loser for a place in the last 16 - either Belgian Ruben Bemmelmans or Estonia's Jurgen Zopp.
Spanish third seed Garbine Muguruza, the 2016 champion, was too strong for France's number 257 Fiona Ferro 6-4, 6-3.
Meanwhile, Australian 24th seed Daria Gavrilova came back from a set and 5-2 down, saving a match point in the process, to defeat America's Bernarda Pera 5-7, 7-5, 6-3.
Later Thursday, Williams, the three-time champion in Paris and playing her first Slam since winning the 2017 Australian Open while two months pregnant, takes on Australia's 17th seed Ashleigh Barty.
All eyes will again be on her striking black catsuit which dominated headlines after her first round win over Kristyna Pliskova and has caused some to question whether or not it's legal.
Manufacturers Nike insisted on Thursday that the suit, which Williams claims also helps prevent the return of blood clots which put her life in danger after giving birth to her daughter in September, will get another airing on Court Philippe Chatrier.
Williams, 36, who is ranked at 451 in the world after her lengthy absence, defeated Barty in their only previous meeting, needing less than an hour to secure a straight sets win at the 2014 Australian Open.
Victory for Williams will take her a step further to a potential last-16 clash with old rival Maria Sharapova.
The Russian, a two-time champion at Roland Garros, is playing in Paris for the first time since 2015.
She missed 2016 while serving a doping suspension and 2017 when organisers refused her a wild card.
Sharapova, seeded 28, had to come back from 0-3 down in the final set to beat Dutch qualifier Richel Hogenkamp in the first round.
On Thursday, out on Court 1, she faces Donna Vekic, the world No 50 from Croatia who has never reached the third round at a major.
Men's top seed and world No 1 Rafael Nadal tackles fellow left-hander Guido Pella of Argentina.
Pella, the world No 78, has never got beyond the second round at the Slams.
Women's top seed Simona Halep, the 2014 and 2017 runner-up, plays big-hitting Taylor Townsend of the United States.
Halep needed three sets to see off Alison Riske in the first round on Wednesday.
Results from day five of the French Open at Roland Garros on Thursday (x denotes seeding):
Marin Cilic (CRO x3) bt Hubert Hurkacz (POL) 6-2, 6-2, 6-7 (2/7), 7-5
Steve Johnson (USA) bt Jan-Lennard Struff (GER) 4-6, 7-6 (7/5), 6-2, 6-2
Fabio Fognini (ITA x18) bt Elias Ymer (SWE) 6-4, 6-1, 6-2
Dominic Thiem (AUT x7) bt Stefanos Tsitsipas (GRE) 6-2, 2-6, 6-4, 6-4
Daria Gavrilova (AUS x24) bt Bernarda Pera (USA) 5-7, 7-5, 6-3
Elise Mertens (BEL x16) bt Heather Watson (GBR) 6-3, 6-4
Garbine Muguruza (ESP x3) bt Fiona Ferro (FRA) 6-4, 6-3
Samantha Stosur (AUS) bt Anastasia Pavlyuchenkova (RUS x30) 6-2, 7-6 (7/1)
Magdalena Rybarikova (SVK x19) bt Belinda Bencic (SUI) 6-2, 6-4