Novak Djokovic was hot and bothered for a time by Salvatore Caruso before moving through to the fourth round of the French Open.
With temperatures in the high 20s after a generally cool and cloudy week, Djokovic did not look comfortable for much of his 6-3 6-3 6-2 victory over Italian qualifier Caruso, which was much tougher than the score suggested.
"It was a different day in terms of conditions," said Djokovic. "It was challenging. Obviously the ball was bouncing differently. In these kind of warmer conditions, the play changes a bit.
"Caruso was very motivated. I thought he stepped into the court having a clear game plan. I kind of stepped it up a little bit. I feel like I took my game to a different level."
Djokovic will next face unseeded German Jan-Lennard Struff, who reached the fourth round at a grand slam for the first time with a five-set win over 13th seed Borna Coric – the fifth set going to 11-9.
Alexander Zverev took the scenic route once again before beating Dusan Lajovic 6-4 6-2 4-6 1-6 6-2.
Of the eight matches the German has played here the last two years, five have gone the distance.
"They didn't explain me the rules of five sets yet, so somebody needs to tell me I don't necessarily need to play five sets every time I step on the court," joked Zverev.
It has been a challenging season so far for the fifth seed, who has long been talked about as the leader of the next generation but has only reached one grand slam quarter-final.
Stefanos Tsitsipas bettered that by defeating Roger Federer and making the semi-finals of the Australian Open, and Zverev, who next faces in-form ninth seed Fabio Fognini, is happy to fly a bit more under the radar this time.
"I think I have been talked about less, which is a very nice thing," he said. "People talk about obviously Rafa, Novak, and all those guys, but Tsitsipas, much, much more. He deserves to have a lot of credit."
Tsitsipas is also through to the fourth round but it has not been easy for the 20-year-old Greek either.
His third-round encounter with Filip Krajinovic had been called off because of darkness on Friday night with Tsitsipas two sets up and at 5-5 in the third.
Serbian Krajinovic took the third-set tie-break on the resumption and had a set point to force a decider but Tsitsipas scraped through 7-5 6-3 6-7 (5) 7-6 (6).
Next for the sixth seed is a tasty-looking encounter with 2015 champion Stan Wawrinka, who finished off his own delayed clash with Grigor Dimitrov, coming from 6-2 down to win the third-set tie-break and the match 7-6 (5) 7-6 (4) 7-6 (8).
The clash was moved on Friday night from Suzanne Lenglen to the much smaller Court One because of an over-running schedule, causing a crush as fans clamoured to see the match.
Wawrinka and Dimitrov played much of the first set to a chorus of booing from outside.
The Swiss said: "I heard the noise yesterday when we were playing for a long time. It's always a tough decision for the tournament, for the crowd, for the players.
"If I just look for myself, being on that court with a full crowd, with an amazing atmosphere, it was really crazy last night and again today. In the last 10 years I didn't play any big match that I remember on this court, and in two days I played something really special that I will remember all my life."
Wawrinka had knee surgery after Wimbledon in 2017 and only now is starting to come back to something like the form that brought him three grand slam titles between 2014 and 2016.
Asked about his hopes of adding to that, the 34-year-old said: "I'm far away from thinking about that here. Do I think or believe I can do it? Maybe. But to win a grand slam, it's a long way, a long road."
Fourth seed Dominic Thiem was a 6-4 3-6 6-2 7-5 winner over Pablo Cuevas and next takes on Gael Monfils, the only man apart from Djokovic and Roger Federer who is yet to drop a set.
The other fourth-round clash in the top half will pit eighth seed Juan Martin Del Potro against 10th seed Karen Khachanov.
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