Novak Djokovic through to US Open second round following eventful match

Making his 19th main draw appearance at Flushing Meadows, Djokovic was quick out of the blocks before he started to struggle and then eventually found his rhythm again to wrap up a 6-1, 7-6 (7-3), 6-2 victory over the American.

In the process, he recorded his 80th win on the famous Arthur Ashe Stadium - the most by a man - with former rivals Roger Federer second on 77 and Rafael Nadal on 64, respectively.

But Djokovic acknowledged that it was a messy performance as he received a second time violation during the second-set tie-breaker, resulting in him losing his first serve, and he went on to lose the point after his second serve.

His first time violation came early in the match and he had an argument with the chair umpire asking, "Did you really have to do that?"

At the end of the set, he required treatment and revealed after the match that he wasn't quite sure what was wrong.

"Well, I started great. Just over 20 minutes, first set, I felt really good. Then some long games to start the second set, and then I start to feel really - I don't know why. I really was surprised how bad I was feeling in the second physically," the 24-time Grand Slam winner said.

"Yeah, we had long exchanges, but also, I kind of dropped my level and made a lot of unforced errors and kind of got him back into the match. I'm glad that I kind of reset myself after second set. And the third one was - the third set was okay to finish up the match.

"There are positive aspects, but also things I hope don't happen, like, for example, how I felt physically in the second set. I hope that doesn't happen again, because then my life on the court will be much more difficult."

Despite the hiccups, he is safely into the second round with a record-extending 75th consecutive Grand Slam first-round win in his 80th Grand Slam appearance.

He will continue his campaign for a fifth US Open trophy in the second round against another American after Zachary Svajda defeated fellow qualifier Zsombor Piros earlier in the day, 6-4, 6-2, 7-5.

Aged 38, Djokovic is happy to have a longer recovery period as he needs to put in some extra work on the court following his decision to skip both the Canadian Open and Cincinnati Open ahead of the season-ending Grand Slam.

"Luckily, I have two days off, but yes, it's a bit concerning. I don't know," he said. "I don't have any injury or anything. It was just very hard for me to stay in long rallies and recover after points.

"In my case, I haven't played an official match in six weeks. In crucial moments, I simply put one more ball in the court than he did."

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