Holger Rune and Beatriz Haddad Maia triumphed in marathon French Open epics which took almost eight hours to complete on Monday while Iga Swiatek required just 31 minutes to move into the quarter-finals.
World number six Rune reached a second successive quarter-final in Paris with his first ever five-set win.
The 20-year-old Dane claimed a four-hour 7-6 (7/3), 3-6, 6-4, 1-6, 7-6 (10/7) victory against Francisco Cerundolo and will face 2022 runner-up Casper Ruud in a repeat of last year's bad-tempered quarter-final.
Rune was jeered by the Court Philippe Chatrier crowd for hitting the ball on a double bounce in the fourth game of the third set.
His 23rd seeded Argentine opponent stopped playing, expecting the umpire to call the point for him.
Play continued and Cerundolo, who was called for hindrance when he halted, dropped serve.
"This is tennis. This is sports. Some umpires, they make mistakes. Some for me; some for him. That's life," said Rune.
Cerundolo, playing in the second week of a Slam for the first time, had the crowd on its feet when he hit back to level the match.
In a dramatic decider, Rune survived being 3-4, 0-40 to hold and then break.
He served for the match at 5-4 but the 24-year-old from Buenos Aires hit back to level for 5-5 and held for 6-5 before the match went to a knife-edge super-tiebreak.
Rune finished the match with 48 winners and 73 unforced errors.
"What a sport," tweeted Cerundolo.
Haddad Maia won the third longest ever women's match at Roland Garros to become the first Brazilian woman in the last eight of a Slam since 1968.
Haddad Maia battled from a set and 3-0 down to defeat Sara Sorribes Tormo in three hours and 51 minutes.
The 27-year-old left-hander came through 6-7 (3/7), 6-3, 7-5 against her 132nd-ranked Spanish opponent on Court Suzanne Lenglen, the venue also for the Rune-Cerundolo clash later in the afternoon.
The match was just 16 minutes short of the record four hours and seven minutes it took Virginie Buisson to beat French compatriot Noelle van Lottum in the first round in 1995.
Haddad Maia is the first Brazilian woman in a Slam quarter-final since seven-time major winner Maria Bueno in 1968.
She will face world number seven Ons Jabeur of Tunisia for a place in the semi-finals.
"I am very happy and very proud that I didn't give up and I think that is why I deserved this victory," said Haddad Maia.
Haddad Maia, ranked 14, who saved a match point in her previous round against Ekaterina Alexandrova, is no stranger to energy-sapping duels.
In Rome last month, she dropped a three-hour 41-minute quarter-final to Anhelina Kalinina — now the second longest women's match of 2023.
Defending champion and world number one Swiatek set-up a quarter-final with Coco Gauff after Lesia Tsurenko retired from their last-16 clash through illness after just 31 minutes.
Swiatek was leading 5-1 when the 66th-ranked Tsurenko, who had called the doctor after experiencing dizziness and shortness of breath, decided not to continue.
In her last round, Swiatek was on court for just 51 minutes in a 6-0, 6-0 blitz of China's Wang Xinyu.
Gauff, 19, reached the quarter-finals for a third successive year with a 7-5, 6-2 win over Anna Karolina Schmiedlova of Slovakia.
Last year Swiatek defeated Gauff 6-1, 6-3 in the final to win the title for a second time.
She holds a 6-0 lead over the American in head-to-head meetings.
"Finals have kind of different rules," said Swiatek.
"Sometimes these matches are a little bit different than the other rounds that we play during the tournament because of the pressure and everything that's going on around."
Jabeur powered into the quarter-finals for the first time with a 6-3, 6-1 rout of Bernarda Pera, breaking the American's serve eight times.
Jabeur, a Wimbledon and US Open runner-up last year, has now reached at least the quarter-finals of all four Slams.
Fourth-ranked Ruud, the runner-up to Rafael Nadal a year ago, beat in-form Nicolas Jarry of Chile 7-6 (7/3), 7-5, 7-5.
The Norwegian saved 14 of 17 break points and now has a tour-leading 85 clay court wins since 2020.