Tommy Paul knocked out top seed Alexander Zverev and Frances Tiafoe downed Felix Auger-Aliassime at the Cincinnati Open.

Paul has slipped down to number 24 in the ATP rankings, but he fought back impressively to overcome Zverev in a weather-impacted last-16 tie.

The home favourite saved a match point en route to a 4-6 7-6 (8-6) 6-4 win, which was interrupted by a long rain shower.

And the upsets continued on Wednesday as another home hope, Tiafoe, got the better of second seed Auger-Aliassime 6-3 6-4.

Tiafoe has now reached his second ATP Masters 1000 quarter-final, having previously done so at the Miami Open. 

It marks the first time 2024 Cincinnati finalist Tiafoe has reached multiple Masters 1000 quarter-finals in the same season.

Arthur Fils beat Alex de Minaur 6-3 6-4 to become the first Frenchman to reach five Masters 1000 quarter-finals in a single season since Jo-Wilfried Tsonga in 2012.

Sixth seed Taylor Fritz did progress, though, as he beat Christopher O'Connell 6-4 6-3.

Brandon Nakashima, meanwhile, overcame Nuno Borges 6-3 6-7 (5-7) 6-3 to become the first player ranked outside the ATP top 20 to reach the quarter-finals in Washington, Montreal/Toronto and Cincinnati in the same season since Andy Murray (2006).

2 - Two Americans (Tommy Paul and Frances Tiafoe) have defeated the top two seeds at an ATP Masters 1000 event for the first time since Toronto in 1998 and for the first time at the Cincinnati Open since 1994. Scalps.#CincyTennis | @CincyTennis @atptour

— OptaAce (@OptaAce) August 20, 2026

Turning up for the stars and stripes 

With Paul and Tiafoe triumphing, two Americans defeated the top two seeds at an ATP Masters 1000 event for the first time since the 1998 Canadian Open.

It is the first time such a feat has been achieved at the Cincinnati Open since 1994.

When asked how he turned his tie around, Paul said: "Not really sure. I guess just put some returns in. He gave me a couple of looks at second serves and a couple of doubles there, that helped me out.

"Then I was just going after the ball a little bit more, going after the second [serve] a little bit more. And I'm having fun out here, having fun."

Paul has now reached 50 Tour-level finals, and he will take on Flavio Cobolli next. The Italian ended Rafael Jodar's run.