Iga Swiatek's overnight turnaround from Cincinnati to New York City

NEW YORK (AP) — Around 8 p.m. Monday, Iga Swiatek was holding up her Cincinnati Open championship trophy.

Around 8 a.m. Tuesday, she was getting ready for her mixed doubles match at the US Open in New York City.

It's been a quick turnaround.

"This was the most extreme situation and most extreme schedule I've had after a title win," Swiatek, currently ranked second in the world, said Tuesday afternoon. "An hour and a half after the match, we already went to catch a plane."

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But that didn't slow her down. Swiatek and Casper Ruud, her mixed doubles partner, won both of their Tuesday matches to secure a spot in Wednesday's mixed doubles quarterfinal, where they'll be competing for a spot in the $1 million title game.

"Actually, it's kind of nice to have another task, and to not let yourself be lazy but really focus on the next exciting thing," she said about the quick turnaround.

Ruud didn't always feel quite so calm about it. He was dining in New York while Swiatek played her title match in Ohio and keeping a close eye on the score. He was secretly chatting with Swiatek's team throughout the match—"she doesn't know this," Ruud said with a laugh—and wondering about their doubles match the next morning.

"I can't lie. I was a little concerned," he said about watching Swiatek continue to progress through the Cincinnati Open's rounds. He exited the tournament in the first round.

"(But) she was here doing her warmup at 10 a.m. … I look at Iga and I'm like, ‘This is determination, like I've never seen it before.'"

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The quick turnaround from Cincinnati is new for singles players at the US Open. With this year's reimagined mixed doubles draw, which includes top singles players for the first time, the week that was usually recovery time is now playing time.

Carlos Alcaraz, the men’s champion in Cincinnati, faced a similar turnaround to his afternoon doubles match with Emma Raducanu. He did have a few more hours on each end, given the scheduling of both tournaments.

Alcaraz was knocked out of mixed doubles Tuesday afternoon, but Swiatek and Ruud will be back in action Wednesday.

"Iga will have a good sleep tonight," said Ruud. "She deserves that."