The Professional Footballers Australia (PFA) has demanded Central Coast Mariners immediately reinstate players after they were issued with stand-down notices amid the coronavirus pandemic.

Last week, the PFA threatened to initiate legal proceedings against Perth Glory owner Tony Sage following his decision to stand down players, with the A-League season on hiatus due to COVID-19.

The Mariners also issued stand-down notices as the league's postponement impacts clubs financially, prompting the PFA to serve Central Coast owner Mike Charlesworth with a letter of demand.

"These actions undermine attempts for our game to overcome common challenges, fight for common interests and re-establish our sport," PFA chief executive John Didulica said in a statement on Tuesday.

"While other codes have fostered unity and demonstrated leadership amid crisis, we are at risk of regressing to the lowest common denominator.

"FFA has indicated an intention to intervene as this matter escalates.

"This morning, we have written to FFA to ask they follow the lead of other sporting codes in this country and lead a collective and uniform solution to our common challenge."

Football Federation Australia (FFA) has already stood down approximately 70 per cent of its staff in a bid to save money amid the coronavirus crisis.

Coronavirus has claimed more than 37,500 lives globally, with over 781,800 confirmed cases.

In Australia, there have been at least 18 deaths and more than 4,350 cases.