Novak Djokovic stretches while bothered by a bad back duirng his third-round win Friday at the U.S. Open in New York. (AP photo)

NEW YORK (AP) — Novak Djokovic shook off a back problem early in the match to beat Cam Norrie on Friday night and at 38 become the oldest man to reach the fourth round of the U.S. Open since Jimmy Connors was the same age in 1991.

Djokovic pulled away to win 6-4, 6-7 (4), 6-2, 6-3, helped by hitting 18 aces in what he said was his best serving performance of the tournament.

The 24-time Grand Slam champion seemed in jeopardy of matching his earliest exit in Flushing Meadows when he needed medical attention near the end of the first set. But he recovered to reach the last 16 of a major for the 69th time, matching Roger Federer for most ever, and will next face German qualifier Jan-Lennard Struff.

The No. 7-seeded Djokovic wouldn’t reveal specifics of his injury in his interview on the court after the match.

“I’m good. I’m as young as ever and as strong as ever,” Djokovic said.

It was during a point at 5-3 in the first set that Djokovic raised his racket awkwardly to reach a volley and immediately showed signs that all was not well. He began trying to stretch his back between points and barely ran for one ball that Norrie hit toward a corner.

After that, Djokovic indicated to the chair umpire that he wanted a visit from a trainer, and soon was walking to the locker room for a medical timeout, clutching at his lower left back. Djokovic returned to the court soon and held serve to take the opening set.

At the changeover at 2-1 in the second set, Djokovic got a back massage while seated on the sideline and also was given pills by a doctor.

It’s the third time at a Grand Slam tournament this season that Djokovic has been hampered after getting hurt during a match — and the second time he had to stop. At the Australian Open in January, he tore a hamstring and was unable to continue after one set of his semifinal against Alexander Zverev.

At Wimbledon in July, Djokovic took an awkward fall in the last game of his quarterfinal victory, tweaking his groin muscle, and while he stayed in the bracket there, he was clearly compromised during a semifinal loss against eventual champion Jannik Sinner.

The U.S. Open was Djokovic’s first tournament since then and he’s had some struggles in each of his first three matches.

“My team wants me to suffer on the court so I can get more minutes of match play,” he joked.

ALCARAZ SURVIVES AILMENTS

Carlos Alcaraz was cruising along in the U.S. Open’s third round, leading by a set and a break after taking 10 of the first 14 games in Arthur Ashe Stadium on Friday, when an awkward step while striking a forehand caused an issue with his right knee.

The No. 2-seeded Alcaraz, who won the first of his five Grand Slam titles at Flushing Meadows in 2022, got broken for the first time in the tournament, then took a medical timeout and had his leg massaged by a trainer. Problem solved: Alcaraz rolled through the rest of the match, never dropping another game, and beat No. 32 Luciano Darderi 6-2, 6-4, 6-0.

It was the first, brief hint of any trouble for the 22-year-old Alcaraz this week — well, other than the hair-cutting mistake by his brother that led to a shaved head.

He didn’t let teasing from Frances Tiafoe about that bother him, and Alcaraz didn’t seem too concerned about what went on with his knee against Darderi, a 23-year-old Italian who was making his debut as a seed at a major.

“I just felt something that was not working good in the knee, but after five, six points, it was gone,” Alcaraz said, describing the visit from the trainer as precautionary. “I’m going to talk with my team, but I’m not worried about it.”

What else happened at the US Open on Friday?

The 82nd-ranked Rinderknech reached the fourth round at a Slam for the first time by defeating Benjamin Bonzi 4-6, 6-3, 6-3, 6-2. Bonzi had won both of his first two matches in five sets, including in a wild one against 2021 U.S. Open champion Daniil Medvedev, who was fined $42,500 by the tournament for his meltdown after play was delayed when a photographer wandered onto the court. Emma Raducanu’s best run at Flushing Meadows since her 2021 trophy ended with a 6-1, 6-2 loss to No. 9 Elena Rybakina. Defending champion Aryna Sabalenka and 2024 runner-up Jessica Pegula advanced, while Barbora Krejcikova beat No. 10 Emma Navarro in three sets. No. 6 Ben Shelton and No. 17 Frances Tiafoe were eliminated, leaving just two American men remaining.

Who is on Saturday’s schedule at the US Open?

Coco Gauff, Iga Swiatek, Naomi Osaka and Jannik Sinner are among the players scheduled to play on Saturday as the third round wraps up.

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