Williams, seeded third, is the highest seed remaining in the women’s draw of the tournament, moved this year from Cincinnati to New York to put players in a coronavirus quarantine “bubble” at the venue that will host the US Open starting on August 31.
Top seed Karolina Pliskova and No. 2 Sofia Kenin both bowed out in second-round openers — and it looked like 23-time Grand Slam champion Williams could follow them before she roared back to beat Rus 7-6 (8/6), 3-6, 7-6 (7/0).
Williams dropped four straight games in the second set against the hard-hitting left-hander, who has never won a WTA title.
After rallying from 0-40 down in the opening game of the third she looked to have turned the tide with a service break on the way to a 3-0 lead.
Serving for the match at 5-3 in the third, Williams was broken to love, Rus winning the next two to give herself a chance to serve it out.
She was broken, and Williams crushed her in the tiebreaker to wrap up a bruising victory in two hours and 49 minutes.
“That was tough. It was a real physical match out there,” said Williams, who tried to pump herself up on the spectator-free Grandstand court with fist-pumping cries of “c’mon” and squeals of triumph and frustration.
“I had a crowd in my head or something,” Williams said. “It was actually funny to me. I don’t know. For me, it was like there was a crowd there.”
It was Williams’ fourth three-set match since she returned at a tournament in Lexington, Kentucky, in the wake of the WTA’s coronavirus shutdown.
But she said fitness work during the downtime had her ready.
“I’m actually super fit and I’m super ready,” she said.
Fourteen aces, including one at 121 mph, helped her cause as she booked a third-round meeting with 13th-seeded Maria Sakkari of Greece, who beat Kazakhstan’s Yulia Putintseva 6-4, 7-6 (7/9).
Two-time Wimbledon champion Petra Kvitova, the sixth seed, joined the exodus of women’s seeds, beaten 2-6, 7-5, 6-2 by fellow Czech Marie Bouzkova.
Eighth-seeded Briton Johanna Konta moved on with a 6-2, 6-0 victory over Belgian Kirsten Flipkens.
With world number one and top seed Novak Djokovic due to launch his campaign Monday, third-seeded defending champion Daniil Medvedev launched his defense with a 6-4, 6-4 victory over Marcos Giron.
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