The global body for player unions in sport has cast doubt on whether the NRL can restart its season on May 28, saying the planned return date is "very ambitious".

Key points: The World Players Association says it is crucial the NRL puts player welfare ahead of its financial concerns

The World Players Association says it is crucial the NRL puts player welfare ahead of its financial concerns It says there needs to be "thorough" protocols in place to ensure the health and safety of NRL players before the season resumed

It says there needs to be "thorough" protocols in place to ensure the health and safety of NRL players before the season resumed The coronavirus shutdown is expected to have a dramatic impact on sport broadcasting in the coming years

The NRL announced almost a fortnight ago it hoped to resume playing premiership matches next month, after it was forced to suspend the season in March because of the coronavirus outbreak.

The league is confident coronavirus infections will continue their downward trend in Australia and it will be safe for all teams to restart the competition by late May.

But World Players Association executive director Brendan Schwab said the NRL must show caution with its proposal to recommence the season.

He said his organisation, which is the international umbrella body for players unions, including the Rugby League Players' Association (RLPA), had many questions about the NRL's plans.

"I think first and foremost this is a public health crisis, and sport has a leadership [role] to play in order to address it," he said.

"We can't be seen to exacerbate the crisis and we certainly don't want to be seen as conveying a message that all young people are effectively immune from the virus and therefore they shouldn't follow the broader public health messages coming from government."

Schwab, who has vast experience with Australian player unions, said it was not only the NRL that needed to be cautious, as he believed it was a "problem for all" sporting organisations.

"The young population itself is showing its vulnerabilities — very severe illnesses and, in some instances, fatalities," he said.

"The reality is we have to prevent this from occurring and I don't believe that the information is there yet that we can be satisfied that it's safe to return to play. May 28 is very ambitious."

RLPA chief executive Clint Newton is being advised by the World Players Association. He is also sitting on the NRL's Project Apollo group, which — on top of dealing with the fallout from Todd Greenberg's resignation as chief executive — is planning for the competition restart and is due to meet again on Tuesday.

"I think we need to have a very thorough process where the players have their own information," Schwab said.

"We're going to do our best to ensure the players — through RLPA and Clint — have that.

"The protocols that need to be in place will have to be thorough and we're still in the process of devising those."

Schwab said sporting bodies must realise plans to return to playing duties had to come second to ensuring player safety, despite the financial pressure facing most competitions.

"What I don't think we can do is be so desperate to get back on the field that we threaten our social license by placing public health or player health in harm's way," he said.

"I think if we do that we will be looking very short-term, very self-centred and I do think that sport could play a long-term reputational price if it takes that approach."

Schwab said the NRL faced several hurdles it needed to clear before it should be allowed to resume its competition.

"What's the access to [COVID-19] testing? What happens if players get injured and they have to exit the quarantine?" he said.

"What happens if a player suffers a serious injury, which would otherwise require surgery — [would] such an athlete get immediate access to the best operation and the best recovery when the public health system is under stress? Is that appropriate?"

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But Schwab said he did not want to suggest the NRL was being irresponsible.

"I think that we are confronting an acute dilemma where — with limited information and operating against the clock — we're having to decide in a certain way between public health and safety and player health and safety, and the economic viability of our league," he said.

"But we're in circumstances where we can only play where we know there is not an unreasonable risk to health and safety."

Sports without assets are 'on their knees'

Schwab said sporting bodies such as the NRL, which did not have assets to provide liquidity, were the ones who were struggling the most.

"It is incredibly disappointing to see sports on their knees. Sports — which are over a hundred years old — on their knees within weeks, if not months, of that crisis breaking," he said.

The Australian Rugby League Commission board, which governs the NRL, will hear a number of proposals on providing a line of credit to the cash-strapped competition.

The AFL's strong supporter base may come into play if there are changes to its broadcast deal. ( AAP: Joe Castro )

Schwab said the coronavirus crisis would fast-track a "dramatic change" in sport broadcasting, which had already begun moving towards streaming services.

He said the sporting bodies that would benefit the most were those with a direct relationship with fans, such as the AFL through its club membership programs.

"Whether that actually increases or decreases revenue remains to be seen," he said.

"But we do worry that some of the great areas of progress in the lead-up to the pandemic — including in relation to women's sport — they may be affected.

"And so it's very important that when sport comes back together that it has a wholistic view, it just doesn't focus on winning today and maximising revenue today.

"I think in Australia there is a focus on rugby league, but you do need to appreciate that every sport league is facing a huge dilemma and is desperate to get back as soon as it possibly can and the players want to play.

"There is a considerable determination to make this work, but sports that have greater liquidity are clearly not under the same day-to-day pressure as those sports which are facing a liquidity crisis."