Celtic assistant boss Johan Mjallby has confirmed Ki Sung-yueng is set to leave the club with the player thought to be in talks with Swansea.
Swansea are thought to be the club in talks with Ki as Michael Laudrup looks to win the race for the talented playmaker.
Mjallby has revealed the 23-year-old is looking to leave the Scottish champions and he was absent again on Monday as the Celtic squad flew out for the first leg of their UEFA Champions League play-off clash with Helsingborgs in Sweden.
"Ki is not travelling," said Mjallby.
"He is keen to move on and the club is in discussion with another club so we have to wait and see what happens. I can't say who the club is.
"There have been a few clubs interested in him but I know for sure there has been one bid for him and I think maybe one or two other bids.
"He is a quality player but on the other hand he is keen to move on so the club needs to do something.
"He was away at the Olympics for a period of time but we will be sorry to see him go."
Asked whether a replacement would be sought were Ki to leave, Mjallby said: "He has not really been a part of the season so far so we have shown that we can live without him, but on the other hand it would be nice to get someone else in if he goes away.
"If quality players leave the club, you want to freshen things up and have competition. But even with Ki here we would like to see some other faces."
Celtic had 10 players missing for the 1-1 draw with Ross County on Saturday, with injuries sidelining Dylan McGeouch (broken jaw), Daryl Murphy, Gary Hooper (both hamstring), Anthony Stokes, Filip Twardzik (both ankle), Mo Bangura (thigh), Rabiu Ibrahim, Paddy McCourt, James Forrest (all groin) and Scott Brown (hip).
Neil Lennon had hoped Brown, McCourt, Hooper and Forrest would all be fit for the match against Helsingborgs and Mjallby believes they are winning their fitness battles.
He said: "We have Scott Brown, James Forrest, Paddy McCourt and Gary Hooper all travelling. We are going to train later on at the stadium and see how they are.
"Some of them were training (on Sunday) and they looked good.
"I am (expecting them to be ready), it is a big game and the players want to be part of that.
"You have James Forrest with his pace, Scott Brown is the skipper, Paddy McCourt can score from nothing, more or less, and Gary Hooper has been banging in goals for us so it would be nice to have all of them fit, but we will have to wait and see."