Reigning Wimbledon champion Carlos Alcaraz was broken five times by Ugo Humbert but regrouped to book a place in the quarter-finals.
Alcaraz had spent nearly four hours on court during a dramatic victory over Frances Tiafoe on Friday and looked in a hurry to progress when he raced into a two-set lead.
Humbert responded with aplomb to break Alcaraz three times to force a fourth set where two more breaks put him 4-3 up.
But the world number three moved through the gears to claim a 6-3 6-4 1-6 7-5 triumph.
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The Spaniard had produced slow starts in his previous three matches, winning first-set tie-breaks against qualifier Mark Lajal and unseeded Aleksandar Vukic before he lost the opener to Tiafoe, but it was a different story this time.
With the Centre Court roof closed in anticipation for wet weather, Alcaraz broke his opponent in the fifth game.
A first set point came and went on Humbert’s serve but a lovely forehand pass by Alcaraz forced a second, which was taken.
Humbert had barely laid a glove on Alcaraz’s service game by this point, but that changed midway through the second set.
A marathon game saw Humbert create four break point opportunities at 2-2.
Alcaraz dug deep to repel the Frenchman, with brilliant net play able to thwart the final chance before he showed the ruthlessness of a three-time Grand Slam champion with a break to take the set.
Humbert sent a simple volley wide to gift Alcaraz the break, with the current Wimbledon champion earning the adulation of Centre Court after he twice scrambled across the baseline to return before a third slide along the grass helped force the error.
History looked set to repeat itself for Humbert, who had lost to Novak Djokovic in straight sets when he last made the fourth round at Wimbledon in 2019, but the left-hander hit back.
Alcaraz was broken at the start of the third and two more followed, the last when Humbert sent a sweet backhand down the line.
The prospect of another five-setter appeared dispelled by Alcaraz, though, when he was able to break immediately into the fourth.
However, it sparked a chaotic period where Humbert broke back and Alcaraz established a 3-1 lead before the world number 16 won three games in a row and was 0-40 during the eighth service game.
Alcaraz produced two aces to clinch a huge hold and a sumptuous forehand bent over the net secured another, which was followed by a decisive break.
Alcaraz brought up match point with a supreme drop shot before another ace, this time only 103mph, sent him through to the last eight.
World number one Jannik Sinner quelled the challenge of big-serving 14th seed Ben Shelton with a 6-2 6-4 7-6(9) victory that sent him into the last eight.
Shelton, who has consistently sent down rockets on the slick turf at the Grand Slam this year, started aggressively under the Court One roof by serving and volleying in a bid to unsettle the Australian Open champion.
Sinner was equal to the task, however, and broke the feisty American twice to comfortably pocket the opening set.
The Italian consolidated an early break in the second set with a booming ace and pulled away for a two-set advantage, as Shelton was left with another battle on his hands having been dragged the distance in each of his last three rounds.
The 21-year-old raised the hopes of fans by breezing ahead 4-1 in the third set but Sinner ran his opponent ragged with his power and precision to draw level after eight games and saved a breakpoint to force a tiebreak.
Shelton came from behind but squandered all four set points he earned, as Sinner held his nerve to secure the win and book a meeting with fifth seed Daniil Medvedev.
Tenth-seeded Bulgarian Grigor Dimitrov pulled out injured in the first set of his fourth-round tie against Medvedev after a lengthy treatment break.
Medvedev has a 6-5 head-to-head lead over the Italian but has lost their last five matches.
Dimitrov looked in good form, racing to a 3-0 lead in the match, before Medvedev broke back. The Bulgarian then slipped on Court One, carrying on for a couple of games that Medvedev won before taking a medical time out after the seventh.
He returned briefly but could not move well and called it a day after the eighth game during which Medvedev served three aces.
Meanwhile, Emma Raducanu was stunned by qualifier Lulu Sun as her encouraging Wimbledon run came to a disappointing end in the fourth round.
The 21-year-old had inspired hopes of more US Open-style heroics by coming through her opening three matches without dropping a set.
But she looked nervous against powerful New Zealander Sun, the first qualifier to make the women’s singles quarter-finals in 14 years, and, despite battling to force a deciding set, slumped to a 6-2 5-7 6-2 defeat.
Left-hander Sun, who had never won a Grand Slam main-draw match before this week and is now on a seven-match winning streak, racked up 52 winners compared with just 19 from Raducanu and will now face Donna Vekic for a place in the semi-finals.
