Celtic are still waiting to find out whether they will have Kyogo Furuhashi available for the rescheduled clash with Rangers.
The top of the table clash has been moved to February 2 after Premiership clubs voted to move the winter break forward.
That couuld create issues of its own for both teams though, with the Africa Cup of Nations taking place plus World Cup qualifiers in North America, South American and Asia.
It seemed Ange Postecoglou would have his star man available as Japan looked set to call up only J League players for their Qatar 2022 qualifiers.
But boss Hajime Moriyasu has revealed he's still waiting for official guidance on that issue.
He will be desperate for his European-based stars including Celtic talisman Furuhashi for their two games against China and Saudi Arabia in Saitama.
But he's admitted he cannot say yet whether he will be able to call up his overseas players until he is guided by the Japanese government.
Moriyasu said: "I am very worried about the situation for the qualifiers.
"I have no choice but to follow the government directives for the games so I have to wait until nearer the ties to decide on the squad.
"We obviously want to select our strongest team and I hope to find a solution to the matter.
"The sooner the situation is concluded, the better it is for me to prepare."
Celtic would also find themselves in the same situation if they sign reported transfer targets, Reo Hatate and Daizen Maeda, who are both set to be called up too.
