Reilly Opelka celebrates winning the second set against Lorenzo Musetti during his...

Reilly Opelka celebrates winning the second set against Lorenzo Musetti during his men's singles second-round match during the U.S. Open at USTA Billie Jean King National Tennis Center on Thursday. Credit: Getty Images/Elsa

Tiger Woods often talked about the ability to win without his "A" game, a key to his overall success.

And that’s what Reilly Opelka did on Thursday at the U.S. Open, putting away scrappy Italian Lorenzo Musetti, 7-6 (1), 7-5, 6-4.

Now it’s not to think that Opelka will ever have the tennis success of golf’s superstar, but in this case Opelka was able to win without his "A" game and was proud of it.

"I thought, actually didn't think I played great, and that's what I loved about it," Opelka said. "I won the match not playing great. I picked up my level, made some nice adjustments on my return. But it started off ugly. I was clutching in the breaker. Stayed tough, I put pressure on him, and that's what I think good players do is they win when they are not playing well."

Opelka won the first point of the tiebreak, that one little point looming big for the outcome.

"That was a turning point, that really was," said Opelka, who is seeded 22nd and is the only remaining American men’s seed in the tournament. "I think the match could have changed completely. If I'm down 1-0, he hits two big serves, 3-0, not playing well, the next thing I'm down a set. That's how crazy our sport is. One little point like that, one shot."

There’s nothing little about the 6-11 Opelka, the 2018 New York Open champ at Nassau Coliseum, one of his two career titles. But he had a rough start growing his game at the beginning of this season and at one point had lost in the opening round of five straight tournaments.

Then he produced his best ever result in one of the ATP’s premier events, the Rome Master, where he lost to Rafael Nadal in the semifinals. That event was on clay, which made it all the more impressive because the surface can dull the impact of his huge serve.

He also made it to the third round of the French Open, losing to Daniil Medvedev, and lost to Medvedev again in the final of the ATP Masters in Montreal last month, another big step.

Opelka wouldn’t be considered in the contender category here, but he has reached the third round for the first time, where he will play Nikoloz Basilashvili, who beat American qualifier Maxime Cressy.

It served Opelka well that he quashed a constant urge to talk to himself.

"I think the key is to just constantly like, for me, to keep calm," Opelka said. "That way my mind can start thinking about what I need to do different. As soon as I open my mouth once, it's a slippery slope, and then I'll be complaining for two hours straight. So I know to bite my tongue whenever I feel that urge and my mind starts working different. It starts looking for solutions."

So far this tournament, he’s found some

Djokovic rolls on

Novak Djokovic’s quest for the calendar year Grand Slam didn’t slow down any on Thursday night. He defeated Tallon Griekspoor of the Netherlands rather handily, 6-2, 6-3, 6-2, in 1 hour, 40 minutes. It was a step up from his opening victory over Holger Rune, but he’s also conserving energy early for the long run to the final.

"I came out with the right intensity, right focus," Djokovic said. "A better performance than a couple of nights ago."

Djokovic had some issues with a fan courtside. " He’s saying something before I hit my shots," he told the chair umpire, who did not take action. Djokovic had stared down the fan after losing a point.

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Barty party continues

No. 1 seed and Wimbledon champion Ash Barty, the clear favorite at the Open, moved into the second round with a 6-1, 7-5 victory over Clara Tauson, a match distinguished only by Barty’s break of Tauson’s serve in the second game of the first set. It took Barty 10 break points to achieve it.

Barty was asked about practicing with other top players, and whether she might try to hold back anything on her shot selection to keep things a secret.

"There are no secrets," she said. "I just play, do it with a smile on my face, and that's all that matters."

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