Second seed Rybakina beat 17-year-old American Thea Frodin, who once played a young Serena Williams on screen, 6-3 6-2.
In the 2021 film "King Richard," Frodin was the body double for actor Demi Singleton, who played the younger Williams sister. Frodin earned the opportunity to audition after winning titles at the 10-and-under level in California and then spent six months working on set.
With fans chanting her name, Frodin fired consecutive aces after facing match point trailing 5-1, then hit another to erase a third match point Rybakina had earned and eventually held serve. Rybakina finally finished the match on her fourth try by hitting an ace of her own, her sixth.
Rybakina is guaranteed to take the No.1 ranking from Aryna Sabalenka if she reaches the semi-finals, or if the two-time defending champion doesn't win the tournament.
The Kazakhstani world No.2 showed few signs of the leg injury that forced her out of the Cincinnati Open last month.
American Madison Keys overcame early jitters to down Russian Alina Korneeva 7-5 6-4 exorcising the demons of her early exit a year ago.
Just months after winning her first grand slam title at the 2025 Australian Open, Keys crashed out in the first round at Flushing Meadows after being overcome by debilitating nerves.
But Keys felt more at home this time around - improving her first-serve from 48 per cent in the first set to nearly 70 per cent in the second.
"Today is obviously tough, because you go back on the court where you had a really tough loss, and to go back out and play another first round, it's always hard," said the 2017 US Open runner-up. "To have that kind of lingering memory is tough."
Keys looked at first as though she would cruise through the match on Arthur Ashe Stadium as she won the first three games but the Russian broke back in the fifth when Keys hit a forehand shot wildly out of bounds.
After trading breaks again, Keys broke her opponent on her third set point with a fine backhand strike and improved her level across the board in a competitive second set.
Mirra Andreeva began her campaign with a comfortable 6-2 6-2 victory over unseeded Indonesian Janice Tjen to keep her bid for a second grand slam title on track.
Andreeva announced herself by claiming this year's French Open title on clay, but she has shown she is no slouch on hard courts.
The 19-year-old, who looked right at home during her run to the mixed doubles semi-finals with fellow Russian Andrey Rublev last week, relied on her power and precision again to dispatch Tjen under the roof of Louis Armstrong Stadium.
"She's not easy to play against," said Andreeva. "I was just trying to talk to my coach to see what we can do better in order for me to feel confident on the court. I was trying to be very aggressive."
with agencies
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