Carlos Alcaraz has been told that he made a “tactical mistake” that may have made the difference in his US Open quarter-final loss to Ben Shelton.

Shelton prevailed 6-7(5), 6-1, 6-3, 1-6, 7-6(7) against Alcaraz at Flushing Meadows to record his first-ever win against the Spanish great, and surely the biggest triumph of his career to date.

Alcaraz led 5-3 and 6-5 in a tense deciding set tiebreak, but he fell just short in a four-hour-and-28-minute contest that finished at 3:33am on Wednesday.

The world No 3, who was the reigning US Open champion, was aiming to win his third crown at the New York major and his eighth Grand Slam title overall.

The 23-year-old was playing his first tournament since sustaining a right wrist injury at the Barcelona Open in April.

Speaking on his Off Court With Greg Rusedski podcast, Rusedski praised Shelton’s willingness to come to the net against Alcaraz.

“Carlos, you saw how far back he was on the return of serve, and Ben was willing to come forward, serve and volley, the movement, the volleys look good,” said the 1997 US Open finalist.

“Thank God we have someone who comes to the net. If you want to stay on the baseline against Alcaraz, you’re going to be second best almost every time.

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“We thought he (Alcaraz) was playing well enough to win, but Shelton proved us wrong and deserves to be back in the semi-finals.”

The former world No 4 went on to assess that Alcaraz made an error by adopting a deep return position for periods of the match.

“I think it was a little bit of a tactical mistake,” said Rusedski.

“I hate to be harsh on it, but if you give Shelton that much time playing that far back, yes, you’re [taking] away the aces, but you’re also not taking any time away from him.

“So, if you think about it, it allows Shelton to have a lot of options, because he can serve and volley, he can get the first strike up if Alcaraz loops it back, and it gives him more time on the ball.

“So, I think I would like to see Carlos try to stand in a little bit more at times like [Jannik] Sinner does, and that’s why Sinner does so well against Shelton — is the way he reads it and he steps in and takes it a little bit earlier.

“When you give Shelton that option, and especially with the cleverness of the tactics of serving and volleying, and coming in, and striking and getting in as quick as you can, it was a good play.

“So, for me, sometimes you give up the aces to get that one or two games where you have a chance to break, because if Shelton’s hitting his spots, it’s almost impossible to break.

“And he went the distance, it came down to one or two points, and Shelton played the big points fractionally better, and also in part just because Alcaraz has been away for so long.

“It has been mighty impressive what the Spaniard has done in his first week and a bit back from tennis after four and a half months.”

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