Rafael Jodar and Alex de Minaur are among the players who will have to endure another night of sleep before igniting their campaigns at the US Open.
Both players were due to play their first-round matches on Tuesday, but due to rain delays in New York, their clashes will be rescheduled for Wednesday.
#NextGenATP star Jodar takes on lucky loser Buyunchaokete, while sixth seed De Minaur faces qualifier Andrea Guerrieri.
Other matches that have been cancelled include Winston-Salem champion Ignacio Buse against Marcos Giron, Botic van de Zandschulp vs. Jan Choinski, Fabian Marozsan vs. Michael Zheng, and Zachary Svajda vs. Daniel Altmaier.
Some matches will resume Wednesday after a late rain delay forced play to be called off for the evening. Francesco Passaro leads Jesper de Jong 6-2, 2-6, 6-4, 1-1 (15/15). Zizou Bergs, seeded 31st, is up on Carlos Taberner 6-3, 3-6, 6-2, 1-1 (40/0). Alex Molcan and Frenchman Benjamin Bonzi had just started, with the Slovakian leading 2-1.