Andy Murray put in a "half-day" on court Friday, taming the legendary serve of Ivo Karlovic 6-1, 6-4, 7-6 (7-3) to post a straightforward win after a pair of five-setters earlier in the week at the French Open.
The second seed got on and off the Lenglen showcase court in less than two hours after his pair of marathon wins lasting more than three and a half hours each.
Karlovic, who fired 41 aces in the previous round, was limited to a modest 14 as Murray got a grip on the biggest serve in tennis, beating Karlovic for the seventh time without a loss.
"I got off to a quick start and Ivo, he fought to the end," Murray said of a 37-year-old opponent who holds the ATP career record of more than 10,000 aces. "He made it tough.
"I was glad to finally win in three sets. I was able to handle his serve, my return is the strongest part of my game.
"But when he's serving well, there's not much you can do. I had to just stay patient and take care of my service games."
Murray improved to 31-8 at Roland Garros, where he has reached three semi-finals. He handed Karlovic his heaviest defeat at a grand slam in four years.
Eighth seed Milos Raonic needed almost three hours to hold off Slovak Andrej Martin 7-6 (7-4), 6-2, 6-3, with the Canadian given painkillers for a problem with a hip.
The opening set took 72 minutes and required seven set points from Raonic, whose big serve was limited to just seven aces while breaking on seven of 19 chances.
On the women's side, Garbine Muguruza absorbed psychic energy from a day of warm weather to reach the fourth round 6-3, 6-0 over Yanina Wickmayer.
The Spanish fourth seed and the rest of the field got lucky as rain which had been forecast on the day held off.
Sixth seed Simona Halep, the 2014 finalist, also advanced, earning a third-round victory against rising Japanese teenager Naomi Osaka 4-6, 6-2, 6-3.
The 18-year-old who was born in Tokyo but grew up in New York, speaks barely any Japanese, but showed that her tennis needs no translation as she put the Romanian through the wringer in the first set of a contest lasting one and three-quarter hours.
Halep, winner of the Madrid clay title three weeks ago, finally prevailed with seven breaks of serve and 23 winners.
Muguruza said that after the cold weather which marked the opening days of the clay-court major, conditions for her match were ideal.
"It was a perfect day, the first match I played, it was so cold," said last year's Wimbledon finalist. "Today everything was easy - you go to warm up. Perfect sun. Then you go to the court, it's beautiful.
"It brings energy also to see that it's a nice day. If it's dark, you're like this (shrugging)."
Two seeds were knocked out as double Wimbledon winner and tenth seed Petra Kvitova lost in an upset to 108th-ranked American Shelby Rogers 6-0, 6-7 (3-7), 6-0.
Kvitova committed 36 unforced errors along with six double-faults in the subpar performance at an event where she has never excelled.
Australian Samantha Stosur won a battle of Roland Garros runners-up, as the 2010 finalist beat 2015 counterpart and number 11 Lucie Safarova 6-3, 6-7 (0-7), 7-5. Romanian Irina Begu defeated Germany's Annika Beck 6-4, 2-6, 6-1 .
"We played some good tennis today," Safarova said, "I was fighting, did very well in the second set, but lost a little bit beginning of the third. She served really well."