Carlos Alcaraz is enjoying a wave of momentum after returning to the sport at the US Open.

Alcaraz missed four and a half months due to a wrist injury, but returned by impressively reaching the quarterfinals of the US Open in September.

He followed that up by winning the Laver Cup with Team Europe and bagging back-to-back ATP 500 titles at the Japan Open and the Vienna Open.

The Spaniard also won his maiden Paris Masters crown by defeating the likes of Ben Shelton, Casper Ruud, and Taylor Fritz en route to the ATP 1000 trophy.

Despite all this, John Isner has suggested Alcaraz needs to improve in a key area in order to continue taking the ATP Tour by storm.

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Speaking on Nothing Major, Isner said: “He can get better. His serve can still get better. I still think his serve can improve so much.”

Isner believes Alcaraz needs to work on his serve in a similar way to how Novak Djokovic did when he reached the middle part of his career.

“You saw Novak [Djokovic] improve his serve in the middle towards late on in his career, and he just went boom,” said the former world No 8.

Isner even believes that Alcaraz’s current serve is not of the quality of one of the best players on the ATP Tour.

“Carlos’ serve, for as incredible as he is, his serve is not a top-10 serve by any means,” he explained, before suggesting it was an anomaly in the Spaniard’s game.

“When you watch him from the back of the court, it is like, ‘How can anyone play this sport better?,” concluded Isner.

Alcaraz’s serve has looked considerably less powerful since his return, which is surely part down to the wirst injury he suffered at the Barcelona Open.

But his serving stats are still very impressive and up there with the very best on the ATP Tour.

His first serve percentage is at 68% for 2026 and he’s won 73% of his points on first serve and 55% of his points on second serve.

He’s won 88% of his games on serve throughout the year, while he has also won 67% of all points on his serve, so the statistics perhaps state that Alcaraz does not need to do anything with his serve.

Alcaraz will continue his season at the ATP Finals and the Davis Cup Finals, before heading off to Brazil to play an exhibition match against Joao Fonseca in December.

He will not get a long off-season at all, as he will be back in action for the Australian Open at the end of January.