New York (AP) - After losing a set, a few insecurities when serving and changing shoes, Alexander Zverev has reached the third round of the US Open.

“I wasn't extremely happy with my game, but in a match like this you have to find a way to win.

There were many things that I could do better, ”said Germany's best tennis professional on Wednesday (local time) after his 7: 5, 6: 7 (8:10), 6: 3, 6: 1 success against the American Grand Slam debutants Brandon Nakashima.

In the fight for a place in the round of 16, the 23-year-old from Hamburg will meet the number 32 seeded French Adrian Mannarino on Friday.

“It will be a difficult match.

He always plays well, especially on a fast surface, ”Zverev told ARD radio.

"It won't be an easy match, but I'm ready for it."

Against 19-year-old Nakashima, Zverev had to fight for almost three hours before using his second match point.

"Such matches happen in a Grand Slam, and I hope that I can do better in the next round," said the seventh in the world rankings.

He struck 24 aces against Nakashima, but also made ten double faults - and suffered noticeably from the extremely humid weather.

Zverev had to change his shoes, "because suddenly there was a small puddle around me with every step," as he described it in the digital press conference.

«I was sweating so hard that water came out of my shoes.

I couldn't move that well anymore, so I just had to change my shoes. "

A few minutes before Zverev, his Davis Cup colleague Jan-Lennard Struff moved into the third round.

There the 30-year-old Sauerlander will again face the world number one Novak Djokovic.

"He serves great, let's see what awaits me," said Djokovic after his win against Britain's Kyle Edmund respectfully about Struff.

Last week, Djokovic had clearly won the quarter-finals of the Masters event, which was moved from Cincinnati to New York.

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