Rested Nadal wishes he hadn't had walkover at US Open

33-year-old Spaniard advanced to the last 16 by defeating South Korean qualifier Chung Hyeon 6-3, 6-4, 6-2

NEW YORK: A rested and healthy Rafael Nadal rolled into the US Open's fourth round on Saturday, wishing he had been pushed harder as he charges after a 19th Grand Slam title.

The 33-year-old Spaniard, who won his 12th French Open title in June, advanced to the last 16 by defeating 170th-ranked South Korean qualifier Chung Hyeon 6-3, 6-4, 6-2.

"I didn't face a break point. That's a positive thing," Nadal said. "And the best thing is without playing great, playing a normal match, I was able to have a very comfortable score. That means a lot of things, positive ones.

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"Now is the moment to push, to make a step forward if I want to give me a chance to fight for the important things. That's what I'm going to try."

Nadal, a three-time US Open champion, said he wished he had been able to play a second-round match against injured Australian Thanasi Kokkinakis instead of advance by walkover and rest for three days.

The injury-nagged star who was forced out of a US Open semi-final last year with knee pain and struggled with a hip injury earlier this season wanted more than six sets under his belt by now on the New York hardcourts.

"You never know what's better or worse, no? From here, the main thing, I am happy to be where I am. I'm in the fourth round, and that's the main thing," Nadal said.

"For me, personally, in some way, I will prefer to play the match. In some way is true that you save energy. So you never know what's the best thing."

Second seed Nadal is concerned about form as much as rest, although he did withdraw from a tuneup event in Cincinnati after winning at Montreal.

"I had the first three or four months of the season very hard, too many issues again, and then it's true that since Barcelona, things have been improving," Nadal said.

"I was able to fix a little bit the body and play more or less with freedom of movements. That's given me the chance to compete at the highest level again.

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"So here I am to try my best and I'm going to put my 100 percent to try to be ready for the next round."

Next up for Nadal is a Monday matchup against Croatia's 23rd-seeded Marin Cilic, the 2014 US Open champion.

"The key is play well. That simple," Nadal said. "If I'm playing well, I'm going to have hopefully my chances to return a couple of points and give me chances.

"Against big servers... chances are not a lot, so you need to be ready to expect a very tough one. But I need to be focused with my serve, as always. I need to be ready to accept the challenge that brings the competition in days like these.

"And I hope to be ready to play my highest level, because that's what I'm going to need."