Crystal Palace manager Patrick Vieira says it would be a "disaster" if growing Covid-19 fears forced football behind closed doors.
New restrictions known as 'Plan B' will come in from Wednesday in England, including fans needing proof of vaccination or a negative lateral flow test to attend Premier League matches.
Vieira opposes the possibility of empty stadiums, a common sight last season.
"This is the worst case scenario," he said.
"From my personal point of view, it is a disaster to play football matches without the fans.
"It is something that is difficult to process and I hope we will not get there because what the game needs is to have fans at the stadium.