Casper Ruud takes on Matteo Berrettini as the US Open quarter-final action kicks off on Tuesday in New York, where the Norwegian seeks to maintain his challenge for the No. 1 spot in the Pepperstone ATP Rankings.
Nick Kyrgios and Karen Khachanov also meet in the last eight at the hard-court Grand Slam. The Australian is looking to back up his stunning fourth-round triumph against 2021 champion Daniil Medvedev.
ATPTour.com previews the quarter-final action on Day 9 at Flushing Meadows.
 Casper Ruud (NOR) vs.  Matteo Berrettini (ITA)
Fifth seed Ruud is exploring new territory in New York, and in more ways than one.
The Norwegian has advanced to the US Open quarter-finals for the first time with a series of battling performances this fortnight, while the fifth seed also knows that victory against 13th seed Berrettini on Tuesday will lift him two spots to No. 2 in the Pepperstone ATP Live Rankings.
The 23-year-old could become the new World No. 1 if he reaches the championship match at Flushing Meadows, but he is wary of the threat posed by Berrettini. Ruud edged the Italian in three sets in Gstaad in July to lift his ninth tour-level title and believes that his ability to counter Berrettini’s huge serve will be key to his chances of a repeat success in Tuesday’s quarter-final.
”When we played in Gstaad it was really fast conditions even though it was on clay, and it was bouncing a lot,” said Ruud, who leads Berrettini 3-2 in the pair’s ATP Head2Head series. “So most of the times I stayed in and tried this strategy, which didn’t work for all the match, but in the end I was able to win some key moments on it.
“Let’s see. You need to obviously guess right sometimes, and sort of see if you can try to read where he’s going.”
Ruud’s previous-best showing in New York, a third-round appearance in 2020, was ended by Berrettini in straight sets. The Italian demonstrated he can also tough things out if required in his fourth-round victory against Alejandro Davidovich Fokina on Sunday, when he prevailed in five sets after three hours, 45 minutes.
That win improved the 2019 semi-finalist’s record at the US Open to 16-4, and he spoke afterwards about the importance of staying on the front foot against Ruud as he seeks to avenge the loss in Gstaad.
“I think the key is to be aggressive before him,” said Berrettini. “I’m going to try to make him run and not gonna run too much. The key I think is to be aggressive, to use my weapons, my serve, obviously my forehand.”
The match is also significant for both players’ hopes of qualifying for November’s Nitto ATP Finals. Ruud currently sits in fourth place in the Pepperstone ATP Live Race To Turin, while Berrettini is in 13th.
 Nick Kyrgios (AUS) vs.  Karen Khachanov
Kyrgios and Khachanov’s sole previous Grand Slam meeting was a memorable one. The Australian needed four hours and 26 minutes to overcome Khachanov in a remarkable 6-2, 7-6(5), 6-7(6), 6-7(7), 7-6(8) victory at the 2020 Australian Open.
Despite producing what he later described as ‘probably the most boneheaded play of all time’ against Daniil Medvedev in the fourth round in New York on Sunday, Kyrgios delievered an otherwise sparkling performance on Arthur Ashe Stadium to down the World No. 1 and set a second meeting at the majors with 27th seed Khachanov.
Kyrgios has found his best level on Tour in recent months, posting 19-3 on the North American hard courts following his run to a maiden Grand Slam final at Wimbledon in July. The Australian says he is feeding off his strong run of results as he chases his first major title in New York.
“Obviously winning helps. I’ve been winning a lot this year,” said Kyrgios after his Medvedev win. “The motivation has been there. It’s easy to train. It’s easier to wake up obviously when things are going great. I was just really sick of letting people down. I don’t know, just feeling like that. I feel like I’m making people proud now.”
Like Kyrgios, the World No. 31 Khachanov has advanced to the quarter-finals in New York for the first time. The 26-year-old outlasted Pablo Carreno Busta in a fourth-round epic on Sunday and is hopeful that he has turned a corner at Flushing Meadows, where he held a 5-6 tournament record before this year’s tournament.
“To be honest, I had in 2018 a really great match against Rafa (a 2018 third-round clash) and good memories,” said Khachanov. “But then after that, not so good performances in New York, so I was a little bit nervous this year because I wanted to do well, and I feel like I’m playing good tennis.”