Carlos Alcaraz has delayed his comeback from his wrist injury by pulling out of the Cincinnati Open, leaving his US Open title defence in doubt.

The seven-time grand slam champion has been out of action since withdrawing from the Barcelona Open in April, missing both his French Open title defence and Wimbledon.

The Spaniard appeared to be stepping up his injury comeback ahead of the Masters tournament in Cincinnati, which is one of the key warm-up tournaments before the US Open.

In the lead up to Cincinnati, the 23-year-old posted videos of himself making a return to court and hitting balls. Alcaraz spent several weeks with his right wrist immobilised in a cast, which has since been removed.

The Cincinnati tournament, which begins on 13 August, has come too soon, however. The tournamet announced that Alcaraz had withdrawn due to an “ongoing wrist injury”.

“We know Carlos is doing everything he can to get back to playing tournaments as soon as possible,” tournament director Bob Moran said. “We wish him the best with his recovery and look forward to welcoming him back to Cincinnati in the future.”

Given the severity of wrist injuries for tennis players and the dangers of developing long-term conditions, Alcaraz has taken a patient approach to his recovery.

Former US Open champions Dominic Thiem and Juan Martin del Porto both had their careers derailed by wrist injuries - so Alcaraz is right to be cautious.

This season, Alcaraz became the youngest man to complete the career grand slam when he beat Djokovic to win the Australian Open for the first time.

With Alcaraz absent from the French Open, No 2 seed Alexander Zverev triumphed at the end of a chaotic tournament to win his first grand slam title.

Jannik Sinner then defended his Wimbledon title, beating Zverev in the final. Alcaraz beat Sinner in last year’s US Open final to win the tournament for a second time.