Naomi Osaka and Madison Keys advance in dramatic US Open second-round matches

Two-time champion Naomi Osaka overcame mid-match mistakes to progress while Madison Keys saved five match points to keep her campaign alive in the US Open second round, as fans eagerly awaited Coco Gauff and Alexander Zverev in the late program.

A perennial fan favourite in New York, Osaka survived an up-and-down affair against Czech Kateřina Siniaková to win 6-2 5-7 6-1, harnessing the mental resolve she has taken years to hone on the court where she claimed her maiden major eight years ago.

"I just told myself that it's an honour to play on this court," Osaka told the crowd at Arthur Ashe Stadium.

"I just want to keep playing in front of you guys if possible."

The 28-year-old Japanese player's match was not the only nail-biter across the sprawling Flushing Meadows plaza, as American Keys mounted an epic comeback against Hungarian Anna Bondár to win 5-7 6-4 7-6 (5) to delight the home fans on the outer courts.

The 2017 finalist sent over a remarkable 34 forehand winners to get the job done and gave all credit to her adoring fans after forcing Bondár into an error at the net on match point.

"That was something, huh?" Keys, 31, told the crowd after the win.

"No stress though — we all knew I had it, right?"

Her compatriot Taylor Fritz had a far easier time, swatting aside Italian Mattia Bellucci 6-0 6-1 6-1, while Amanda Anisimova's 6-3 3-6 6-1 defeat of Austrian Lilli Tagger added to the American joy.

Canadian third seed Felix Auger-Aliassime, a semi-finalist last year, took the first set but was then swept away in a 6-7(5) 6-3 6-2 6-2 defeat by Russian Karen Khachanov, becoming the highest-seeded man to exit the tournament so far.

The Philippines' wildly popular Alex Eala capped the early programme at Louis Armstrong Stadium with a comprehensive 6-1 6-4 defeat of Ukraine's Oleksandra Oliynykova.

Days of stubborn rain gave way to sunny skies in New York, where Iga Świątek enjoyed a relatively drama-free 6-3 6-2 win over Argentina's Nadia Podoroska, in a rare appearance on the outdoor courts for the 2022 champion.

Fans will eagerly await another evening programme packed with talent as fourth-seeded 2023 champion Gauff kicks off the night on Ashe against Paula Badosa, followed by the men's top seed Zverev, who plays France's Quentin Halys.

Frenchman Gaël Monfils will hope to make magic again in his farewell season when he faces 14th-seeded American Learner Tien in the first night match at Armstrong before second seed Elena Rybakina plays Spain's Jessica Bouzas Maneiro.