Holding Grand Slams in costly ¡°bio-bubbles¡± may not be sustainable for a second season despite the financial edge the majors enjoy over other tournaments, ATP chief Andrea Gaudenzi has told Reuters.

The sport¡¯s big four tournaments have not been immune to the impact of the COVID-19 pandemic, with Wimbledon canceled for the first time since World War II last year and the most recent editions of the other three held in bio-secure environments.

¡°Most of them run a federation as well so they¡¯re also in charge of tennis development throughout the country,¡± Gaudenzi, the chairman of the men¡¯s tour, said recently.