Start time: 12:00 p.m. ET, 9:00 a.m. PT; TV: ESPN, tennis channel

Jannik Sinner (1) against Alex Michelsen

World number one Jannik Sinner will have to contend with a home win against Arthur Ashe for the second time in a row. He got off to a rocky start against Mackenzie McDonald, but recovered to easily beat Michelsen’s compatriot.

Michelsen, meanwhile, beat qualifier Eliot Spizzirri, who had already played one of the tournament’s matches before the main draw began when he beat Joao Fonseca to qualify for the main draw. Michelsen made short work of him, but Sinner is a whole different order of magnitude.

Iga Swiatek (1) versus Ena Shibahara

Iga Swiatek edged another qualifier, Kamilla Rakhimova, but made 29 unforced errors in the second set, which went to a tiebreak. The subtlety, versatility and controlled aggressiveness that characterized her game when she burst onto the scene in 2020 have essentially disappeared, and that leaves her vulnerable.

Shibahara, ranked 39th in the doubles world rankings, won a match tiebreak to defeat Australia’s Daria Saville after winning two other three-set matches in qualifying to advance to the main draw of a Grand Slam tournament for the first time.

Naomi Osaka (WC) against Karolina Muchova

A two-time US Open champion faces last year’s US Open finalist in what could be the match of the day, between two players – both unseeded, both returning from time off – with different playing styles and fantastic personalities.

Osaka has already reminded the tennis world of the appeal of her superstar status, while Muchova produced the shot of the tournament on day two.