Gordon Taylor has revealed playing less than 45 minutes per half has been proposed ahead of the return of football in England.
There has been no professional football in England since mid-March due to the coronavirus pandemic, and players' union boss Taylor does not envisage a return until at least the middle of June.
The Premier League launched 'Project Restart' in a bid to conclude the 2019/20 campaign, with games potentially played at neutral venues in England or even overseas.
World governing body FIFA has proposed increasing the number of substitutions in an attempt to ease players' workload, with the prospect of a hectic schedule to come if the action gets under way again.
Professional Footballers' Association (PFA) chief executive Taylor says reducing the duration of matches has also been discussed.
He told the BBC Radio 4 Today programme: "We don't know the future, what we do know is what propositions have been put, what ideas have been put, the possibility of having more substitutes, games possibly not being the full 45 minutes each way.
"We've talked of neutral stadiums, there's lots of things been put forward, try and wait and see what the proposals are and then have the courtesy to let the managers and coaches and players come to a considered view."
Taylor believes it would be unrealistic to expect games to take place before the middle of next month.
He added: "I wouldn't expect games to be played, if everything was positive and promising, you wouldn't be thinking of matches being played until around about the middle of June."
Manchester City striker Sergio Aguero said players are "scared" to return and Taylor stated it is their choice over whether they take to the field.
The long-serving PFA boss said: "Sergio is a top-class player and is entitled to his opinion of course.
"It's not a question of being scared, it's a question of being fully informed and for the relevant authorities to try and make sure it's as safe as it possibly can be to return, and to pick out any particular statements or choose any parts of that process is not really fair until we've looked at the whole menu."
Taylor added: "They are professional sportsmen and professional sportswomen and of course they are concerned about their own safety, they are not stupid and neither are they naive, so they have to be satisfied that it is safe to return and it is their choice."