HONG KONG — Carlos Alcaraz added his voice to the criticism and pulled out of the Shanghai Masters with “physical issues” as the packed schedule for elite tennis players came under renewed scrutiny this week.

With another season approaching its climax, six-time major champion Alcaraz and fellow Grand Slam winners Iga Swiatek and Coco Gauff all took aim at the amount of tennis they play.

The busy calendar in women’s and men’s tennis has been a constant talking point in recent years.

Top players, who earn handsomely, have repeatedly railed against their workload and this week saw a raft of matches end prematurely at the China Open.

Five players retired from their matches in Beijing with injury on Monday alone.

On Tuesday there was the sight of Daniil Medvedev hobbling about on court, barely able to move, before the Russian called it quits when 0-4 down in the deciding set of his semi-final to US teenager Learner Tien.

Tien’s quarter-final opponent, Lorenzo Musetti, also retired with injury.