Novak Djokovic ends US Open hopes of promising 20-year-old American Jenson Brooksby – USA TODAY

NEW YORK — There aren’t many people on planet Earth who are up to the sheer physical effort it takes to beat Novak Djokovic in a best-of-five set match. 

Maybe one day, when 20-year-old American Jenson Brooksby’s body fully matures and he can add a few miles per hour to that serve, he’ll have the tools to be one of them. Because for nearly two hours under the lights at Arthur Ashe Stadium on Monday, the youngster from Sacramento showed what was possible. Then, in a 45-minute sprint to the finish line, Djokovic showed who’s boss. 

It certainly wasn’t easy for Djokovic, trying to complete the exceedingly rare calendar Grand Slam, to neutralize Brooksby’s unconventional game break his willingness to fight past the point of exhaustion. But eventually, as most do, Brooksby could only go on so long as Djokovic pulled away to a 1-6, 6-3, 6-2, 6-2 victory that sends him into a quarterfinal matchup Wednesday against No. 6 seed Matteo Berrettini. 

Novak Djokovic reacts after a fourth-set winner against Jenson Brooksby on Day 8 at the US Open.

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“We had some very, very long rallies, long games,” Djokovic said. “It took a toll physically I think on both of us. But I managed to find the right serves. I served efficiently when I needed to, opening up the court. The third and fourth set were really, really good from my side. I felt I was more dominant. It was a good finish. It wasn’t a good start. But all in all, expected the battle, and I got that one. I’m pleased to overcome it.”

Not too often has Djokovic had to work so hard this early in a Grand Slam to win a match that failed to go five sets and didn’t even feature any tiebreakers. Then again, he’s only lost a set as lopsided as 6-1 five times in his entire history at the majors. 

But that’s the level of complication Djokovic had to deal with from Brooksby, who just recently moved into the top 100 in the rankings after reaching the final at Newport in July and the semifinals in Washington in August, earning some high-quality wins over the likes of two-time Grand Slam finalist Kevin Anderson and No. 15 Felix Auger-Aliassime.

Along the way, Brooksby has developed a reputation as a tricky opponent whose technique would not be taught at many youth clinics but combined with his intelligence, feel and hustle has put him at the front of the wave of exciting American prospects just starting to make inroads on tour.

All of that, combined with the pressure on Djokovic as he gets ever closer to a record 21 major titles, set up an interesting scenario at Ashe, where the fan support for Djokovic during this tournament has been tepid to the point of annoyance. 

In fact, though, when the night session began Monday, it was Djokovic who got the far larger ovations against a player mostly unknown to the crowd here. It didn’t take long, however, for them to figure out what Brooksby is all about. 

In a display that seemed to stun and disorient Djokovic, Brooksby came out flying around the court, using his athleticism and quick hands to return shots that would normally draw errors and drawing Djokovic into rallies that clearly flustered him. By the time the first set was over, Djokovic had made 11 unforced errors to Brooksby’s one and given the fans something far different than the blowout many of them expected. 

“I really did have a lot of confidence in myself out there that I can beat him, I can beat anybody,” Brooksby said.

In a way, though, what happened in the second set likely earned Brooksby more admiration both from the crowd and his fellow players despite ultimately losing it, 6-3. 

When Djokovic inevitably raised the level of his game to begin the second set, hitting his groundstrokes with more pace and accuracy while accepting that he was going to have to win long rallies, Brooksby didn’t back down. 

In fact, after getting broken for the first time in the match and immediately falling behind 3-0, Brooksby fought his way back in an epic, 20-minute game that featured 24 points, brutally physical rallies and six break chances before Brooksby finally got back on serve. 

Though Djokovic looked exhausted as he dumped a backhand into the net on the final point and staggered back to his chair, Brooksby had paid an even bigger price. As the match went on, he said he was struggling with a hip issue that had popped up in a previous match here. 

“Not like it’s an excuse or anything, but it kind of went throughout the leg today a bit,” Brooksby said. “I was struggling more to push off and move. But that’s part of the sport. I did everything I could to feel best I can going out there today and all the other days. There’s no regrets on that. I definitely think if there wasn’t that, I could have kept a better level up closer to the first set throughout the rest of the match.”

In some ways, though, that illustrates why it’s so difficult these days for players of Brooksby’s age to survive in the Grand Slams. By the time Monday’s match began, Brooksby had already played a lot of tennis, coming from two sets to one down in the third round against Aslan Karatsev and playing four-set matches against both Mikael Ymer and Taylor Fritz that lasted more than four hours. 

For somebody who had never played more than two matches at his three previous Grand Slam appearances, it was an awful lot to ask. And ultimately, it wasn’t sustainable against an opponent like Djokovic, who immediately broke back at 3-2 and stared down Brooksby for several seconds as he ran down a high-quality drop shot and ripped a cross-court winner to close out the game. 

“I really wanted him to feel my presence on the court,” Djokovic said. “I wanted the energy to shift on my side because he was a better player for a set and a half. He had the momentum. He had me on the back foot. I felt like that was the point where, ‘Okay, now I got him.’ I wanted to wear him down, and it worked.”

From there, Brooksby didn’t have quite enough game or energy for one more legitimate push. His serve, which is not a strength yet, let I’m down in a just a couple key moments, which is all it took for Djokovic to gain some separation early in both the third and fourth sets. At this age, and at this stage of his development, Brooksby didn’t have anything left in the tank by the end.  

Still, Djokovic was highly complimentary of his opponent and told him how much he admired the performance during a long exchange at the net. 

“He’s 20. He’s got plenty of time,” Djokovic said. “He showed also, I think, mental maturity on the court. Stepped in, and considering the circumstances, his first Arthur Ashe Stadium match, against me, night session, I think he managed himself very well. He was motivated and did his best. I have to congratulate him and say that I was impressed with his game, but also with his behavior.

“Yeah, I think we’re going to see a lot of him in the future. He has the means. Now, obviously a lot of things have to come together, but he has a bit of an unorthodox game, does a lot with the feel. But he’s smart. He knows how to win points.”

For his part, Djokovic still has not played his best tennis at this U.S. Open, losing sets to Brooksby, Kei Nishikori and Holger Rune. It’s possible he’s working up to his peak in the second week, but at age 34, he doesn’t want to play too many matches like Monday where nearly every point for three-plus hours was a battle. 

In Berrettini, Djokovic faces an opponent he’s knocked out of the last two majors — in the quarterfinals of the French Open and in the Wimbledon final, both of which were highly competitive matches. It’s fitting he’ll have to beat him one more time this year if the calendar Slam is indeed his destiny.

“Look, if he serves well, which is his biggest weapon, he’s tough,” Djokovic said. “He’s tough on any surface to play against. I’ve had some really close matches with him in French Open and Wimbledon recently. We’re going to play the third Grand Slam in a row against each other. Hopefully the result will be the same like the previous two.”