Alexander Zverev defeated Holger Rune at 01:40 local time in Paris to reach the French Open quarter-finals with a thrilling five-set win.
The fourth seed needed four hours and 40 minutes to edge past Rune of Denmark 4-6 6-1 5-7 7-6 (7-2) 6-2.
It was the second match in three days that finished in the early hours of the morning at Roland Garros after Novak Djokovic wrapped up a five-set victory against Lorenzo Musetti at 03:07 on Sunday.
Zverev will face Alex de Minaur in the men’s fourth round after the Australian beat fifth seed Daniil Medvedev earlier on Monday.
On Sunday, US Open champion Coco Gauff said tennis matches finishing at 3am were “unhealthy”.
Zverev and Rune were supposed to be on court at 20:15 local time but did not begin their warm-ups until after 21:00.
The previous match on Philippe Chatrier between Djokovic and Francisco Cerundolo lasted four hours and 39 minutes.
Zverev was playing in Paris under the shadow of an ongoing trial in Berlin relating to allegations he assaulted an ex-girlfriend, which he denies.
German Zverev, 27, is still hunting his first Grand Slam title and has fallen at the semi-final stage of the past three French Opens.
He was broken midway through the first set by 13th seed Rune, who then saved three break-back points on his way to taking the first set.
Zverev cruised to the second with three breaks but lost his serve at the end of the third, hitting a volley wildly off target when defending set point.
The pair broke each other twice in a gripping fourth set which Zverev took with a decisive tie-break.
In the fifth set Zverev maintained control, breaking twice to reach his 12th Grand Slam quarter-final.
Fourth seed Medvedev stunned by De Minaur
IMAGE SOURCE: GETTY IMAGES
Image caption: Daniil Medvedev was playing in the French Open fourth round for only the third time in eight appearances
Daniil Medvedev became the highest seed to fall in the French Open singles after losing to Australia’s Alex de Minaur earlier on Monday.
The Russian fifth seed, 28, was beaten 4-6 6-2 6-1 6-3 in the fourth round.
He needed treatment for blisters on his feet in the second set and lost nine of the next 10 games when he returned from a medical timeout.
The former world number one, who has never gone past the French Open quarter-finals, improved in the fourth set after going off court again.
But a poor backhand into the net handed over a breakpoint at 3-3, which De Minaur took spectacularly with an inside-out forehand winner that kissed the line.
De Minaur used his speed around the court superbly to keep points alive throughout and drew mistakes out his frustrated opponent.
With Medvedev chuntering to his team, De Minaur stayed composed to hold to love and move a game away from victory.
Medvedev mis-hit a forehand long behind the baseline at 30-30 5-3 and a double fault from the 2021 US Open champion on match point was a sorry way to finish.
De Minaur is the first Australian man to reach the Roland Garros quarter-finals since Lleyton Hewitt in 2004.
Having never previously gone beyond the second round in Paris, De Minaur screamed “I love the clay! I love it here!” as he celebrated.
Throughout the match the 25-year-old was again spurred on by a young super-fan, who he credited for helping him beat Jan-Lennard Struff in the third round.
De Minaur said he was inspired by seeing the boy enthusiastically cheering every point and tracked him down on social media to invite him to this match.
The youngster was sat close to De Minaur’s team with a couple of friends, and all three chanted, cheered and celebrated after every point in the Australian’s favour.
De Minaur said he would invite the fan to his quarter-final match, adding: “I might have to get him on tour week in, week out.”