Rafael Nadal has moved ominously into the last 16 at the US Open with a straight-sets win over Chung Hyeon.

The Spanish second seed made light work of South Korean qualifier Chung, winning their third-round match 6-3 6-4 6-2 in just under two hours on Saturday.

With fitness doubts hanging over defending champion and world No.1 Novak Djokovic, and third seed Roger Federer looking susceptible in his earlier rounds, Nadal must sense a huge opportunity to add to his three titles here.

The draw has certainly been kind to him with both his great rivals on the other side, while second-round opponent Australia’s Thanasi Kokkinakis was forced to withdraw through injury.

It meant that while Chung, a former Australian Open semi-finalist who has slipped to 170 in the world due to injuries, had already spent 11 hours on court this week, Nadal had spent just two.

Nadal had also dispensed with the tape he usually has strapped around his knees, which have given him so many injury troubles in the past.

“The tape is not working any more,” he explained.

“But I’m happy to be playing on the hard court. I’m trying to play a bit more aggressive. I’m happy to be in the fourth round one more time.

“Last year I had some tough matches and in the semi-final I had to retire. This year I had to miss some tournaments, I’m not 25 anymore.

“You never know what’s better or worse, all that matters to me is I’m in the fourth round. I just think day by day, try to practice and be ready for a tough match.”

Nadal will face either Marin Cilic or John Isner in the last 16.

Also on Saturday, Pablo Andujar beat Alexander Bublik of Kazakhstan 6-4 6-3 6-2 to reach the last 16.

The unseeded Spaniard will face either France’s Gael Monfils or Canada’s Denis Shapovalov in the next round.