The Saudi Arabian club was left with only 11 fit players for their final group stage match but,under the AFC's rules,they were deemed to have withdrawn from the competition and all their previous results were declared null and void. A-League players and coaches see no reason why the virus couldn't penetrate their bubble in Doha in the same way.

The clubs are also worried about the financial,logistical and mental health implications of another round of quarantine upon their return to Australia,the timing of which is entirely dependent on how far they go in the ACL.

Shouldany of the teams progress past the round of 16 they will be facing the prospect of spending Christmas in self-isolation,which would further complicate planning for the new A-League season commencing on December 27.

All three clubs will have to serve their quarantine periods in Sydney but,according to club sources,have been told by the NSW government they will need to hire out an entire hotel as well as pay for security and police to escort them to training facilities each day – all up at a cost of nearly $500,000.

Sources also indicate there are no guarantees that foreign A-League players or staffers who are not citizens or permanent residents will be granted re-entry into Australia,and no definitive answer on whether current insurance policies will cover lost income for players or coaches if they were to contract COVID-19. Anyone who does test positive prior to departure would have to remain in Qatar until they return a negative result.

FIFA has rules in place allowing clubs to block national team call-ups for players if they are subject to lengthy quarantine periods,but they don't apply to international competitions within the realm of club football.

The AFC is desperate to complete the Champions League to avoid repaying tens of millions of dollars to broadcasters if it were to be called off,while A-League clubs would likely be slapped with a heavy fine and suspension from ACL by the confederation at minimum if they were to withdraw.

All three clubs are keen to play in principle but believe that doing so under the current circumstances is nigh on impossible,at least without some form of assistance – financial or otherwise – from FFA or AFC.

An FFA spokesperson said the governing body was in"ongoing discussions"with the AFC,the three A-League teams and other national associations regarding planning and logistics for the ACL.

In a statement,the AFC said the"safety of everyone involved"remained their highest priority and that the completed West Zone fixtures gave them a"blueprint"to follow in conjunction with local authorities.

"Similarly in the AFC Champions League (East),we will ensure that all players and officials be tested before and upon their arrival in Qatar and we will also extend these tests to be conducted every three to six days throughout the duration of the tournament in accordance with the medical guidelines,"the statement said.

"This will further complement the bio-secure bubble in place,which controls and limits the movement of players,teams and match officials to minimise any possible risks and to ensure the safety and wellbeing of all stakeholders."