New York - Rafael Nadal wants to be forever young, but the world number one will probably have to settle for tennis immortality.
The 31-year-old Spaniard advanced to his 32nd Grand Slam quarter-final and seventh US Open last-eight on Monday by defeating Ukraine's 64th-ranked Alexandr Dolgopolov 6-2, 6-4, 6-1 for his 50th Open match win.
The 15-time Grand Slam champion, who had not made the US Open last eight since capturing the 2013 title, will next face Russian 19-year-old Andrey Rublev, the youngest quarter-finalist since Andy Roddick in 2001.
Rublev could become the youngest US Open semi-finalist since Australian Lleyton Hewitt in 2000 and the youngest Slam semi-finalist since Nadal at the 2005 French Open on the way to his first major title.
"Of course if I can come back to 19, I take it," Nadal said. "A lot more years to enjoy the tour, a lot more years to enjoy the life. Of course, better be 19 than 31.
"I always wanted to be young. Even when I was 8 years old, I was not very happy, when it was my birthday, to be 9. Still the same. I am 31 and I am not happy when my birthday going to be 32.
"I am happy being young, no? I don't want to get older. For the moment, I didn't find the way to stop that watch."
In a year where Nadal appears to be turning back the clock, he has won his record 10th French Open title and fallen to Roger Federer in the Australian Open final.
Nadal would, however, like to ease the load on his aging body and future stars by not playing so much on hardcourts like those he is cruising to victory upon in New York, although he says they give him less trouble now than Wimbledon grass.
"Is a little bit easy to play here than on grass," Nadal said.
"But at the same time, I feel this surface is much more aggressive than grass or clay. For the hip, for the knees, for the ankles, for the back."
Nadal warns it could hamper the longevity of Rublev and other rising young stars.
"Is true that the players are playing longer, but at the same time, young players are playing a lot on hard and I don't know if that's going to be very healthy for the future," Nadal said.
"Is something that is difficult to change, because is true that the tournaments on this surface are probably easier to maintain and probably less expensive for the organization, but at the same time, is not for me today but is the most aggressive surface for the body."
Rublev says he has nothing to lose against Nadal, but the 2010 and 2013 US Open champion knows that is youthful bluster.
"He's young, but at the same time, he's in quarterfinals. He has a chance to be in the semifinals for the first time and I've been there couple of times. So of course he has things to lose," Nadal said.
"And of course I have things to lose and things to win. But I tell you one thing. This sport is about victory. This is not about defeats. At the end of your career, nobody remember your defeats, your losses. People remember the victories. For everybody is everything to win.
One thing Nadal doesn't want to lose is his chance to face Federer in the semi-finals, what would be their first Grand Slam meeting in New York.
"You can ask me about that in two days if I am here with victory and I will answer you with a lot of great pleasure if that happens," Nadal said.