Celtic defender Mark Wilson could be out for up to eight weeks with the knee injury sustained in the 1-1 draw against Rangers at Ibrox last Sunday.
Wilson cost Celtic £500,000 in January from Dundee United
The former Dundee United player broke his foot against Manchester United in the Champions League in September.
However, the 22-year-old only returned against FC Copenhagen at the beginning of December.
But the former Scotland Under-21 international could now be sidelined for another two months.
The experienced Paul Telfer will provide cover for the injured Wilson and manager Gordon Strachan does not expect to bring in another right-back.
"It is disappointing for all of of us because Mark is a superb player, but it happens in a player's career," said Strachan.
"But we handled it without him, so we hope we can do it again.
"We have targets but we will not be forced into any panic buying."