Three-time US Open champion Rafael Nadal was handed a walkover in his second round match on Thursday at the year’s final Grand Slam.

The Spaniard advanced without striking a ball when injury-plagued Australian Thanasi Kokkinakis pulled out of their scheduled evening tie on Arthur Ashe with a right shoulder problem.

The Spanish 18-time Grand Slam winner will meet South Korean qualifier Chung Hyeon for a spot in the last 16.

Nadal’s path to a fourth title, already helped with “Big Three” rivals Novak Djokovic and Roger Federer on the opposite side of the draw, cleared further having already seen four top-10 rivals dumped out in the first round.

Chung was involved in a five-set thriller against Fernando Verdasco of Spain. The Korean made an incredible comeback from two sets down to win the match 1-6, 2-6, 7-5, 6-3, 7-6 and advance to the next round.

Alexander Zverev, the sixth seed, is the highest-ranked player remaining on his side of the draw, as the German survived a second successive five-set marathon by outlasting American Frances Tiafoe 6-3, 3-6, 6-2, 2-6, 6-3 to equal his best US Open run.

Fifth seed Daniil Medvedev, coming off a maiden Masters title in Cincinnati, was struck down by cramp during a 6-3, 7-5, 5-7, 6-3 win over Bolivia’s Hugo Dellien.

“I’m not sure what happened today and why I started cramping suddenly,” Medvedev said. “I obviously thought at one point ‘How did I win?’ I don’t know how I did.”

Stan Wawrinka, the 2016 US Open champion, beat Jeremy Chardy in four sets and is on a fourth-round collision course with Djokovic, while Australian 28th seed Nick Kyrgios rolled past 104th-ranked French wildcard Antoine Hoang 6-4, 6-2, 6-4.

(With AFP inputs)