PARIS -- Waking up early Friday for his third-round match at the French Open, Dominic Thiem was surprised to see the morning skies were still dark.
Yup, Roland Garros in autumn, when the sun is slower to rouse itself than during the usual May-June slot, takes some getting used to. But the US Open champion is adjusting just fine to the peculiarities of what is now the last Grand Slam tournament in a pandemic-hit year.
The runner-up last year and in 2018, both times to Rafael Nadal, advanced to the fourth round for the fifth consecutive time, with another straight-sets victory at Roland Garros in this year's first encounter between seeded men.
The victim of the third-seeded Austrian's fierce backhand and super-quick court coverage under the new roof on Court Philippe Chatrier was No. 28 Casper Ruud, dispatched 6-4, 6-3, 6-1.
Long after early bird Thiem was done, Nadal also marched on in his pursuit of a 13th French Open title and record-tying 20th major overall. His opponent, Stefano Travaglia, was among five Italian men in third-round play, an Open Era record at a Grand Slam. But he proved no match for Nadal's overpowering clay-court game. Nadal was on court for just 95 minutes, winning 6-1, 6-4, 6-0.
Sebastian Korda, Nadal's next opponent, is the 20-year-old son of 1998 Australian Open champion Petr Korda. Korda and his third-round Spanish opponent Pedro Martinez reached the main draw via the qualifying tournament. Korda won 6-4, 6-3, 6-1 to become the first qualifier to reach the men's fourth round since Alejandro Falla in 2011.
The 2015 champion, Stan Wawrinka, fell to French wild card Hugo Gaston, who wrapped up the 2-6, 6-3, 6-3, 4-6, 6-0 win with spectators' cries of "Hugo! Hugo!'' ringing in his ears. Ranked 239th, Gaston next plays Thiem.
Thiem, who is 27 and is bidding to become the first Austrian with multiple Grand Slam titles, has said he loves the chilly conditions that other players have grumbled about at this year's pushed-back French Open.
Still, waking up in the players' bio-secured hotel at 7 a.m. for the first match Friday on Chatrier, he was taken aback that dawn had yet to break, as it would have done in May.
"Everything dark. Winter is almost coming," he said. "That was a little bit weird."
Thiem was broken only once, when he sent a forehand wide to give Ruud a 3-1 lead in the first set. He immediately broke back and converted six of his 15 break points in all. He also saved seven of the eight break points he faced.
Ruud was bidding to become only the second Norwegian man to reach the fourth round of a Grand Slam.
The first was his father and coach, Christian Ruud, at the Australian Open in 1997. He watched Friday on Chatrier.
The other men's matchups on the draw's bottom half: No. 6 Alexander Zverev, the runner-up to Thiem in New York, against 19-year-old Jannik Sinner, and No. 12 Diego Schwartzman against Lorenzo Sonego.
It took 36 points in a marathon third-set tiebreaker for Sonego to finally shake off 27th-seeded American Taylor Fritz.
Sonego eventually won the tiebreaker in the 1-hour, 18-minute third set and won the match 7-6 (5), 6-3, 7-6 (17).