Defending women's champion Naomi Osaka has bowed out but men's second seed Rafael Nadal marches on.
And wild card Kristie Ahn's dream run came to an end against Elie Mertens while Alexander Zverev ran out of steam against Diego Schwartzman.
Here, PA looks back at day eight and forward to day nine at the US Open.
Shot of the day
...AROUND...................THE.............................NET! An absolutely unreal winner to set up match point... 🔥🔥@RafaelNadal | #USOpen pic.twitter.com/TRJZ44h8ES — US Open Tennis (@usopen) September 3, 2019
Wow! Nadal brought up match point against Marin Cilic with this amazing around-the-net number.
Shock of the day
At the moment, @BelindaBencic is in the zone 👊#USOpen pic.twitter.com/OxWr0iMWit — US Open Tennis (@usopen) September 2, 2019
Belinda Bencic had already beaten world number one and defending champion Osaka twice this year, but few expected win number three to come at Flushing Meadows.
Stat of the day
Osaka's defeat means she will lose the world number one spot to Ashleigh Barty after the tournament.
Quote of the day
Kids taken to school
Puddle Tennis......starring @CocoGauff and @CatyMcNally. @usopen pic.twitter.com/sxolS1Q9JY — judy murray (@JudyMurray) September 2, 2019
Teenage doubles duo Coco Gauff and Caty McNally were handed a 6-0 6-1 lesson by the experienced Barty and Victoria Azarenka.
Fallen seeds
Men: Alexander Zverev (6), Marin Cilic (22)
Women: Naomi Osaka (1), Julia Goerges (26)
Brit watch
Johanna Konta is first up on Arthur Ashe on Friday as she bids to become the first British woman in the Open era to reach all four grand slam semi-finals. In the mixed doubles Jamie Murray and American Bethanie Mattek-Sands beat Mate Pavic and Gabriela Dabrowski in three.
Order of play
There's something about that New York crowd for @DaniilMedwed... 😉 Medvedev makes first quarterfinal: https://t.co/VF3mCwMy0R#USOpen pic.twitter.com/YUjwHXXZdw — US Open Tennis (@usopen) September 2, 2019
Arthur Ashe Stadium:
Johanna Konta v Elina Svitolina
Stan Wawrinka v Daniil Medvedev
Serena Williams v Wang Qiang
Roger Federer v Grigor Dimitrov
