World No. 3 Alexander Zverev accused tournament directors of slowing down courts to help Carlos Alcaraz and Jannik Sinner succeed across all surfaces, with the German saying on Saturday that the sport needs to bring back variety.

Zverev was speaking at the Shanghai Masters, where he was asked to give his thoughts on the court speed on the tour this year, which others like Swiss great Roger Federer have also observed to be slower.

Federer said the slower courts allow players to play the same way on clay, grass or hard courts, adding that he wanted to see Alcaraz and Sinner adjust to fast conditions.