Celtic manager Neil Lennon has stated that winger James Forrest is highly likely to miss out on the crunch match at home to Spartak Moscow on December 5.
The youngster has been out since his club's 2-0 loss to Kilmarnock on October 27 and is fighting to be fit in time for the clash in which the Hoops must better Benfica's result against Barcelona to qualify for the knockout stages.
"James Forrest had a scan on Monday and it has come through that he has got a tendon problem in the hamstring area," Lennon told Sky Sports News.
"It always seems to be a complication with James, none of his injuries seem to be straightforward. We hope, and it's an outside chance, he'll be fit for Spartak."
The 41-year old has also proclaimed that he will rest members of his squad prior to the Spartak match in order to ensure that his team do not suffer from fatigue, which was an issue against Benfica in the club's last Champions League game.
He said: "I'm going to have to use the squad for these upcoming games.
"We need players who haven't played as much as they would like to really come to the fore and make sure our league form is consistent, so we go into the Spartak game ready to go."