Celtic have made a €3 million offer for Besiktas defender Dusko Tosic according to Fanatik.

Per the source, the Black Eagles want at least €4 million for the Serbia international.

The Istanbul giants strengthened their defensive line recently signing Croatia international Domagoj Vida.

Besiktas are not keen on losing Tosic in January but are aware his advancing age means this could be the last chance they have to cash in.

Tosic struck up and impressive partnership with Pepe for Besiktas this season, excelling in the Champions League.

The 32-year-old made the fourth highest number of interceptions in the group stage – second if you take players who featured in every group game.

Besiktas became the first Turkish side to book a place in the Last 16 stage as group leaders after topping Group G.

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Tosic has established himself as a fan favorite at Besiktas and is keen on staying until at least the end of the season.

The former Portsmouth man has one and a half years remaining on his contract.

Tosic was a full-back but has been converted into a centre-back this season.