Super Eagles defender Efe Ambrose is believed to be a target for German Bundesliga side Bayer Leverkusen.
According to HeraldSport, it is believed Ambrose is high up on Bayer Leverkusen’s wanted list with representatives in Germany already preparing a £1.5m bid.
The 27-year-old currently has a year left to run on his contract at Parkhead but Celtic will be reluctant to part with Ambrose without having someone coming in to replace him quickly ahead of a crucial stage of their season.
The Scottish champions begin their Champions League qualifiers next week without Dedryck Boyata, Jozo Simunovic – who are both injured and Charlie Mulgrew, who is yet to agree a new deal.
There was no sign of Ambrose yesterday as Celtic won 1-0 away to Sturm Graz in what was their second game of their pre-season training camp.
Meanwhile, visa issues have halted Ambrose meeting up with his team-mates who flew out to Maribor on Monday night.
Reacting to Ambrose’s absence new Celtic boss Brendan Rodgers said: “We’re still waiting to hear on whether he’ll be here. We’re just waiting on that.
“Well, having as many players as possible helps. But the boys who are out here are doing very well. We talk about the aggression in our defending and I was pleased with our corners tonight.
“We talked about having that bit of steel when we’re under pressure from a set piece.
“We defended that well, had good organisation. And, all round, our central defenders are coping well.”