MASON, Ohio — Defending champion Karolina Pliskova pulled off a doubleheader sweep Friday at the Western & Southern Open, reaching the semifinals by winning a pair of matches with little rest in-between. Rafael Nadal couldn't do the same.
Pliskova completed a match that was suspended overnight because of rain, beating qualifier Camila Giorgi in three sets. After a quick turnaround, she needed only 67 minutes to beat a rested Caroline Wozniacki 6-2, 6-4 for a sweep into the semis.
"The first match helped me a little bit to have some rallies already today," Pliskova said. "Physically it was not that tough, so I was warmed up enough."
Nadal got only halfway there.
He spent an hour and 37 minutes on court in the afternoon while beating fellow Spaniard Albert Ramos-Vinolas in a match carried over from the previous night. Five hours later, he was back on court against Nick Kyrgios, who had won a three-set match earlier in the day.
Nadal was sloppy at the outset and on the defensive for much of a 6-2, 7-5 loss that lasted an hour and 20 minutes.
"No excuses, nothing at all," Nadal said. "I didn't play well."
Despite the loss, Nadal will move back to No. 1 in the ATP rankings next week for the first time since 2014, before a series of injuries affected his game.
"To be No. 1 after all the things I've been going through the last couple years is something unbelievable," Nadal said. "For me, it's an amazing achievement."
After the match, Nadal wore a ribbon honouring the victims of the attack in Barcelona that left 13 people dead.
"A tragedy," he said. "The feeling that you're not safe nowhere — that's terrible. It's very sad and I'm very, very sorry about what happened. To all the victims, the families, friends — all my support."
Kyrgios will face David Ferrer, who won his only match of the day — 6-3, 6-3 over fourth-seeded Dominic Thiem. At age 35, Ferrer is the second-oldest semifinalist in Cincinnati during the Open Era behind Ken Rosewall in 1970.
No. 7 Grigor Dimitrov is the top seed left in a men's field depleted by upsets and injuries — Roger Federer, Novak Djokovic, Andy Murray and defending champion Marin Cilic missed the tournament because of injuries. Dimitrov needed only 52 minutes to beat Yuichi Sugita 6-2, 6-1.
He'll face John Isner, who beat wild-card Jared Donaldson 7-6 (4), 7-5. Isner won the only break point of the match to go ahead 6-5 in the second set. He closed it out with a 136 mph ace, one of his 25 in the match.
"I knew that a lot of the conditions and everything about this tournament, my schedule — a lot of things have worked in my favour this week," Isner said. "So I hope to keep it going."
In the women's bracket, Pliskova will face Garbine Mugaruza in the semifinals. The Wimbledon champion survived another tough challenge on Friday, beating Svetlana Kuznetsova 6-2, 5-7, 7-5. The match went 2 hours, 45 minutes — her longest of the tournament.
"I think it was one of the best matches of the year," Muguruza said. "I think we both played very well, especially in the third set. I know I won, but I'm sure she feels like it was a great match as well, because it was a tough battle and very hot out there."
Muguruza's win came less than 24 hours after she spent 2 hours, 18 minutes on the court and fought off three match points to beat Madison Keys in the round of 16.
Muguruza has reached the semifinals of two of the three tournaments she's entered since winning Wimbledon.
"You know, I'm happy with the way I'm playing and the way I'm going through these tough matches because, you know, I've got to dig in and somehow win them," she said.
Sloan Stephens also pulled off a two-win day to reach the semifinals. She beat Ekaterina Makarova in three sets, and then ate lunch, took a nap, woke up and knocked off Julia Goerges in straight sets.
"The day is just like a blur," Stephens said. "I'm ready to get dinner and get in bed because I'm so tired."
On Saturday, she'll face No. 2 Simona Halep, who beat Johanna Konta 6-4, 7-6 (1).
"I played the best match so far this tournament," said Halep, who was slowed by a knee injury earlier this season. "I could hit the ball. I could move well. So I feel the rhythm. It's back. So I'm positive again."
AP freelance writer Mark Schmetzer contributed to this report.