2019 US Open Men's Results, Day 4: Zverev sees off Tiafoe in five-set battle, Nadal receives walk-over

Zverev was taken to a deciding set for a second consecutive match in seeing off the American 6-3 3-6 6-2 2-6 6-3. It was a topsy turvy affair which saw the sixth seed hit 52 unforced errors as the balance of the tie was very much up in the air throughout.

Rafael Nadal was the lucky player of the round with a walk over which meant he didn't have to play Thanasi Kokkinakis who withdrew with a right shoulder injury. He will now take on the resurgent Chung Hyeon in the next round.

Nick Kyrgios though produced the goods at Flushing Meadows with the so called bad boy of tennis giving an exhibition of serving as he eased through against Antoine Hoang of France.

He ended up victorious 6-4, 6-2, 6-4 with 24 aces throughout the tie. The 28th seed will now take on Andrey Rublev who similar to Nadal received an easy route through as Gilles Simon retired but this will be a hotly anticipated tie for sure.

Daniil Medvedev finally recorded his 16th win in his last 18 matches in seeing off Hugo Dellien of Bolivia 6-3, 7-5, 5-7, 6-3. There was similar to Tsitsipas a few days back problems with cramping seemingly the issue.

It seems that the amount of tennis the Russian ace is playing is catching up with him and next up will be Feliciano Lopez as he aims to continue his stunning form.