No play was possible at the Italian Open on Wednesday because of persistent rain in Rome.
Four-time finalist Roger Federer was due to make his first appearance at the event since 2016 against Joao Sousa.
World number one Novak Djokovic was due to play Denis Shapovalov in the evening but play was finally abandoned for the day at 8.30pm local time.
Britain's Johanna Konta and women's world number one Naomi Osaka were also thwarted by the elements.
Konta is drawn against American world number eight Sloane Stephens, while Osaka faces Dominika Cibulkova.
They will all be part of Thursday's day session, which will now be split into two parts.