Lorenzo Musetti vs Giovanni Mpetshi Perricard
17:00 CET, Louis Armstrong Stadium.
Musetti's form from last year has dipped, and the injury he picked up at Roland Garros didn't help his well-being. However, even though he crashed out in the first round at Wimbledon, he's still a top 10 player.
Unfortunately, his effective style of play on grass that has helped him beat Mpetshi Perricard twice, he will not be able to use on the American hard courts.
Musetti has won only one match out of four on hard courts this summer, so the chances of success for his big-serving French opponent are pretty high. It promises to be an intriguing contest.
Stefanos Tsitsipas vs Alexandre Muller
20:30 CET, Court 7.
Tsitsipas has won just one match at Grand Slams this year and the hope of him staying near the top of the world rankings is slowly fading. The confidence of the Greek is also damaged by the fact that he has not won back-to-back matches since April on clay.
He has the ability to play on hard courts, having won the Masters tournament in Dubai in March, but somewhat surprisingly, he has never progressed beyond the third round in New York.
That's why Muller has a great chance of success in their first-round clash. This year, he has established himself in the top 50 and has plenty of tools that could trouble Tsitsipas.
Coco Gauff vs Ajla Tomljanovic
01:00 CET, Arthur Ashe Stadium.
While Gauff failed to win a single match on grass this year, she's back on the American hard courts and should be full of confidence after winning the US Open two years ago. Furthermore, this year, she added a second Grand Slam title in Paris and is the best hope for a home champion.
The first round should be relatively straightforward for Gauff; Tomljanovic used to have better seasons and she hasn't fared well against the absolute top players - she has won only one of her 13 head-to-heads against top three players.
Gauff is therefore the favourite, despite the fact that she struggled to go deep in Montreal and Cincinnati, and also changed coaches just before the US Open.