Celtic take on AEK Athens in a crucial Champions League qualifier this evening. They do so without defender Dedryck Boyata in their squad.
The Belgian was also missing for the defeat to Hearts at the weekend. His absence is amid reports that he is refusing to play for the club.
Boyata reportedly wants to leave Glasgow. His agent questioned on Monday why Celtic were turning down offers for his client. If they are so financially well-off as to reject bids, then why have they not offered "a dignified new contract proposal" asked Jacques Lichtenstein.
The 27-year-old has since denied that he is refusing to play for the club, tweeting out a video of himself receiving treatment for an injury.
"Muscular work session to come back even stronger on the pitch," wrote Boyata.
Unfortunately I could not play tomorrow because I'm not yet 100% operational but I'm with all my teammates to bring the qualification.
He also spoke to Belgian website DH.be.
"When I hear I've refused to play since I came back from vacation, it's wrong.
"Last Thursday, I hurt myself when I slipped in training and I held my leg immediately.
"The physio saw it and examined me right after the session. I put ice for 30 minutes on my leg and, the next day, I specified I had pains.
"The exams proved I could not play against Hearts and, since then, I'm doing everything I can to be ready as quickly as possible."