We take a look at four potential candidates who could leave Celtic in the January transfer window.
Celtic manager Ronny Deila has admitted that he may have to sell players before he can bring any in during the January transfer window.
The size of the Bhoys' squad means it is already proving a struggle to keep everyone happy and the Norwegian says that getting rid of some of his fringe players will be a priority in the new-year.
"We have to see what is available, but it is also about money," he said to the Scottish Evening Times. "We have a lot of players, and have loaned some out, too, for the rest of the season."
"We have to find the right balance between having a good enough and big enough squad to be in four competitions, but, we don't want to have too many here because then some players do not feel involved in the team."
In this piece we take a look at four Celtic player's whose futures at Parkhead are at risk because of Deila's planned clear-out.
Nir Biton appeared a firm part of Deila's first-team plans when he initially arrived at the club, but the Israeli international midfielder has found his opportunities in the starting line-up more limited recently.
Biton has not played a league game for the Bhoys since October 18, with his only appearance since coming against Hearts in the Scottish FA Cup.
At 23, Biton still has time to develop, but his progression is unlikely to be helped if he is not having the chance to play and Celtic may chose to move him on for the good of the club and the player at the next possible opportunity.
The experienced midfielder has been linked with a move to the Premier League and doubts around his future are starting to grow.
Kris Commons was a vital part of the Celtic side who won the league last campaign, but Deila seemingly doesn't view him as such a key player.
The Bhoys boss has refused to offer Commons a new long-term deal because of his age and the attacking midfielder has delayed committing his future to the club, as a result.
His departure would be a massive disappointment for Celtic fans, but it is looking more and more likely because of the lack of progress being made with his contract talks.
Things have not worked out for Leigh Griffiths since he arrived at the club at the start of 2014.
The striker has struggled to make an impact and nearly left in the summer to join Hibernian.
In the end, Griffiths decided he wanted to stay and fight for his place, but he has been unable to dislodge John Guidetti or Anthony Stokes in the starting line-up.
Most of his appearances have come from the substitutes' bench and, after scoring just three times to date, an exit looks imminent.
Occasionally brilliant, but too often anonymous, Derk Boerrigter has failed to string a run of good performances together at Celtic.
He can be a match-winner on his day, but his skill in possession is often undone by his lack of end product.
The Dutchman has struggled with injuries throughout his career and his failure to stay off the treatment table has also harmed his chance of being a success with the Bhoys.
He has played just three times this season under Deila and is one of the leading candidates to leave Parkhead in January.