By ANDREW DAMPF AP Sports Writer
ROME (AP) — Rafael Nadal put away Fernando Verdasco 6-4, 6-0 at the Italian Open on Friday to reach the semifinals after conceding only six games in his six sets of tennis at the tournament.
Yet he ought to be a little nervous.
Nadal has fallen in the semifinals of his last three tournaments — all on his favored clay. And next up is Stefanos Tsitsipas, whom Nadal lost to in Madrid last week.
"I know what happened last week, and I (am) going to try to do it better tomorrow," Nadal said. "I have to hold the level or increase a little bit more. If that happens, I (am) going to have my chances. The good thing is during the last month my feeling is every week was better than the previous one."
Tsitsipas, 20, is up to No. 7 in the rankings.
"Every year, we make (a) prediction with the team which player is going to be at the top 10 at the end of the season," Nadal said. "I put Tsitsipas there. ... He started even better than what I (expected). He deserves to be where he is now."
Top-ranked Novak Djokovic outlasted Juan Martin del Potro 4-6, 7-6 (6), 6-4 in an entertaining slugfest that lasted more than three hours and finished after 1 a.m. local time at the Foro Italico.
Djokovic saved a match point in the second-set tiebreaker and was frustrated at times, receiving a warning for slamming his racket to the clay early in the third. But the Serb regained his composure and closed it out by serving an ace on his first match point.
Djokovic next faces Diego Schwartzman, who beat Kei Nishikori for the first time in four tries, 6-4, 6-2, to reach his first Masters Series semifinal.
Meanwhile, Roger Federer and top-ranked Naomi Osaka withdrew before their quarterfinals because of injuries.
Federer reported a right leg injury ahead of his match against Tsitsipas, and Osaka said she'd mysteriously woken up with a sore right hand ahead of her scheduled match against Kiki Bertens.
On the women's side, Karolina Pliskova rallied past former No. 1 Victoria Azarenka 6-7 (5), 6-2, 6-2 and will face qualifier Maria Sakkari, who came back to beat Kristina Mladenovic 5-7, 6-3, 6-0.
Bertens, who won the Madrid Open last week, will face Johanna Konta, who beat Marketa Vondrousova 6-3, 3-6, 6-1.
Although Osaka won both of her matches on Thursday in straight sets, Federer, 37, had to labor for more than 2 ½ hours to overcome Borna Coric in his second time on court.
Federer said after beating Coric that he slid on a wet line and his leg "was hurting a little bit."
"I am disappointed that I will not be able to compete today. I am not 100 percent physically and, after consultation with my team, it was determined that I not play," Federer said. "Rome has always been one of my favorite cities to visit and I hope to be back next year."
Later, Federer wrote on Instagram: "The fan reaction and crowd energy during my matches yesterday remind exactly why I am still competing on the ATP Tour."
It's only the fourth time in Federer's career he has had a walkover loss, the ATP Tour said, adding the 20-time Grand Slam champion has never retired in 1,465 matches.
Osaka couldn't immediately say how serious her injury is or if it will affect her status for Roland Garros, which starts in nine days. She had yet to see a doctor, but when she held her hand up for reporters, it was clearly swollen.
"I woke up this morning and couldn't really move my thumb," Osaka said. "I tried to practice and grip my racket but I couldn't, and I kept feeling this pain when I tried to move my hand in different directions."
Osaka's win on Thursday guaranteed she will remain No. 1 going into the French Open.
"I didn't feel anything yesterday. That's why I'm kind of confused right now because I literally woke up in the morning and couldn't move my thumb," Osaka said. "So I was like, 'Maybe I slept on it and maybe it will go away.' But it didn't."
Osaka also withdrew before a semifinal in Stuttgart, Germany, last month due to an abdominal injury, and she retired from her previous meeting with Bertens at last year's WTA Finals with a leg injury.
"I feel like the ab thing could have been helped, but this one I don't think I could have helped it because I don't know what caused it," Osaka said. "I don't know why I have it."