Bayer Leverkusen have made contact with the agents of Celtic defender Kristoffer Ajer, according to reports in the Scottish media.
The Norwegian international is expected to leave Parkhead this summer, with his contract running down into its final year, and there has been interest from a number of different teams.
In addition to Leverkusen, Newcastle have been tipped to make an £8m bid for Ajer in recent weeks, while newly-promoted English Premier League side Norwich are also said to be keeping tabs on the 23-year-old.
Whether any of the three teams will make a formal approach for the centre-back, we shall have to wait and see. If the Norwegian is unwilling to sign a contract extension, the Hoops will be keen to get as much money as they can so it can be reinvested into the squad.
Ajer is one of three key players, along with Ryan Christie and Odsonne Edouard, who are likely to be offloaded, with the trio not willing to put pen to paper on new deals.