South Korean tennis player Chung Hyeon advanced to the third round at the U.S. Open after a dramatic come-from-behind victory.

Chung, ranked the world's number 170, defeated the 34th-ranked Spaniard Fernando Verdasco taking three last sets at Billie Jean King National Tennis Center in New York on Thursday.

Chung rallied from a four-to-one deficit in the fifth set and saved a match point to force a tiebreak.

He then charged out to a five-nil lead before finishing off Verdasco seven-to-three in a match that lasted three hours and 21 minutes.

The 23-year-old will face the world's number two and three-time U.S. Open champion with 18 Grand Slam singles titles, Rafael Nadal, in a round three match Saturday afternoon or early Sunday morning in South Korea.

This is the third time Chung has reached at least the third round at a Grand Slam tournament, after the 2017 French Open and the 2018 Australian Open.