New York: On the American Labour Day holiday, US Open defending champion Carlos Alcaraz went to work and eased past Italian Matteo Arnaldi 6-3, 6-3, 6-4 on Monday to reach the quarterfinals.
Through the first week of the season's final Grand Slam, the world No. 1 has been putting in routine shifts and dropped only one set en route to the last eight.
But the second week is the business end of a Grand Slam when the draw has thinned out and serious contenders surface.
In Alcaraz's rear view mirror are relative unknowns, like Arnaldi and Dominik Koepfer, but further ahead lurk familiar danger men such as Russians Daniil Medvedev and Andrey Rublev.
He will next face 12th seeded German Alexander Zverev. Former US Open runner-up Zverev beat sixth seed Jannik Sinner 6-4, 3-6, 6-2, 4-6, 6-3 late on Monday.
Alcaraz has not shown his best yet on the New York hardcourts but like a hot Wall Street stock the Spaniard is trending in the right direction.
There have been a few hiccups and lapses but the 20-year-old's raw talent, power and repertoire of weapons make him the man to beat and he is on track for another showdown with arch-rival Novak Djokovic.
Under a closed roof on Arthur Ashe Stadium, Alcaraz was solid from the start against a man who was playing in the Flushing Meadows main draw for the first time.
It took a few games for Alcaraz to size up his opponent but once the Spaniard did it was pretty much one way traffic.
Alcaraz took charge with a break for a 4-2 lead in the first set and then broke again at the start of the second to find himself 2-0 up.
The feisty Italian had his moment in the third set, breaking Alcaraz at 2-1, but the Spaniard immediately broke back and then broke again to seal victory.
Later Arnaldi confirmed what most already knew - he could see no holes in Alcaraz's game.
"(I) try to not let him find weakness to my game," said Alcaraz. "I try to put him to the limit every time that I can in every match, against every opponent.
"I try to put my own game, try to put my style on the match.
"I'm happy that he said that because I'm doing great things on the court."
After two late-night matches at Flushing Meadows third seed Medvedev finally finished work 'early' on Monday by taming Australian Alex de Minaur 2-6, 6-4, 6-1, 6-2 to move into the quarterfinals for the fourth time in five years.
Medvedev has been working the graveyard shift at the US Open, with his previous two matches starting one day and ending early the next, but after a sluggish start he stepped into high gear to speed past 13th seeded De Minaur.
"Today, first set felt like he couldn't miss," said Medvedev. "I was missing just a little bit too much.
"I felt like he was playing top level.
"I was like, Wow, he's actually destroying me right now, that's why the score.
"To turn around the match like this is always a great feeling. It gives you a lot of confidence for next matches."
Medvedev, the 2021 champion, led their head-to-head meetings 4-2 coming into the match but the Australian had won their last two contests, including a straight sets quarter-final win at the Canadian Open tune-up event.
De Minaur looked like he might make it three straight after taking the opening set on Louis Armstrong before Medvedev found his comfort zone.
Finally starting to dictate play, the Russian broke to win the second and stepped up the pressure in the third to move in front before calmly closing out a comfortable win.
Next up is a quarterfinal against compatriot Rublev, who is godfather to Medvedev's daughter.
"I think we're really close friends ... we have a great relationship," said Medvedev. "To have a friend like this is great but on the court we both want to win.
"We're not going to be friends in two days."
Second seed Aryna Sabalenka eased past Daria Kasatkina 6-1, 6-3 to make the quarterfinals for the third year in a row on Monday, subduing her opponent with her powerful forehand inside Arthur Ashe Stadium.
Australian Open champion Sabalenka will rise to the top of the WTA rankings when they are updated after the tournament and was playing with the confidence of a world No. 1 as she pounded Kasatkina with 31 winners.
Kasatkina lost in straight sets to the Belarusian last month in Cincinnati and had clearly not cracked the code, as Sabalenka overwhelmed her at every turn.
"I think I'm playing great tennis," Sabalenka told reporters. "But there is always things to improve. There is always things to keep building and keep getting better with every match you play."
Sabalenka next faces China's Zheng Qinwen, who knocked out 2022 finalist Ons Jabeur in straight sets.
Zheng stunned last year's runner-up Ons Jabeur in the fourth round with a 6-2, 6-4 win over the Tunisian fifth seed at Louis Armstrong Stadium.
Illness had left Jabeur struggling to catch her breath at times earlier in the tournament and she looked exhausted against Zheng.
"I always believe that I'm able to beat everyone if I play the right tennis that I have to play," said 23rd seed Zheng, who called Monday's win a "breakthrough".
"I believe that if I'm really there fighting for every point, I mean, things (are) going to happen."