Mikael Lustig has left Celtic facing a defensive sweat after leaving the field during Sweden's Euro 2020 qualifier.
The defender was substituted after just 24 minutes of his country's Group F clash against Romania.
His fitness worry follows Dedryck Boyata 's withdrawal from Belgium duty while Kieran Tierney nurses a knock ahead of next week's showdown with Rangers.
Lustig was replaced by Amiens fullback Emil Krafth, before Sweden went on to take a 2-0 lead through Robin Quaison and Viktor Claesson.
The knock comes just hours after Boyata mysteriously dropped out of the from the Belgium squad for "personal reasons".
The official Belgium Twitter account announced his withdrawal alongside that of keeper Matz Sels, who they said had a shoulder injury.
However, there has been no indication that Boyata is injured.
But there is concern over Tierney as he was ruled out of Scotland's defeat to Kazakhstan before dropping out of the squad altogether.
Now Neil Lennon - who has admitted the international break is an anxious time for managers - faces a wait to see if his players are available for selection against Rangers.
Dedryck Boyata mystery as Celtic star withdraws from Belgium squad
Lustig operated at centre back as Celtic needed a stoppage time winner against relegation battlers Dundee last weekend.
Jeremy Toljan has been the preferred choice at right back in recent weeks.
