Dedryck Boyata has mysteriously withdrawn from Belgium duty for "personal reasons".
The Celtic defender has dropped out of the squad to face Cyprus in a Euro 2020 qualifier on Tuesday.
Boyata's drop-out comes just a week before the Hoops take on Rangers in a crucial Premiership clash.
Record Sport Online understands he's still set to face Steven Gerrard's side but the reason for his international call-off remains unclear.
The centre-back missed the win over Dundee prior to the international break but played 90 minutes for his country on Thursday.
He took up his role at the heart of defence as the Red Devils defeated Russia 3-1.
Boss Roberto Martinez hinted the following day he may turn to Thomas Vermaelen ahead of Boyata for the trip to Cyprus.
But there was no indication that the 28-year-old would drop out of the squad altogether.
Celtic interim boss Neil Lennon has admitted that the international break is an anxious time for managers as they wait for players to return unscathed.
However, there's no suggestion as yet that Boyata is injured.
The official Belgium Twitter account announced his withdrawal alongside that of keeper Matz Sels, who they said had a shoulder injury.
But there was no such revelation for Boyata.
Elsewhere, Mikael Lustig has suffered an injury scare as he was substituted less than 25 minutes into Sweden's meeting with Romania.
Kieran Tierney is also a fitness doubt for the visit of Steven Gerrard's side - he withdrew from Scotland duty on Thursday.
