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Celtic could be ready to step up their chase to sign another centre-back after it was revealed that new signing Marvin Compper has picked up a calf injury and could face a month on the sidelines.
Twitter: Brendan Rodgers says new defender Marvin Compper is out for 3-4 weeks with a calf injury. Expects to make new sig… https://t.co/38zwi0MepK (@ClydeSSB)
According to the Daily Record, Celtic are interested in signing Dusko Tosic from Besiktas and Turkish reports claim that the Scottish Champions have made a bid of around €3 million.
However, the Turkish reports also say that the Super Lig giants have told Celtic they must increase their offer to around €4 million to land Tosic.

The Serbian defender is much like Marvin Compper in terms of experience and is also the same age at 32. Tosic is naturally a centre-half but can also move to left-back.
Tosic has been capped a total of 21 times by his country and also played in all six Champions League group stage games for Besiktas.
Speaking to the media last month, the Serbian claimed he was happy with life in Istanbul but would also understand if the club chose to sell him.
I have been receiving offers for the past couple of years.
In truth, I am very happy in Istanbul. I am enjoying the best time of my life here. We win titles, we are challenging with the best teams in the world and have brilliant fans.
I want to stay at this great club unless the board has different plans for me. I Â respect their decision but if they don’t want to sell me then I’m definitely staying here and will fight for my Jersey.
If Tosic was to make the switch to Glasgow it would definitely be no downgrade as, like Besiktas, Celtic are regularly competing for trophies, are also involved in European football and have a world-renowned fan base.

With the recent departure of Erik Svaitchenko to Midtjylland and the aforementioned injury to Marvin Compper, the Hoops may be slightly lighter in the defensive areas, so this January window could be the time where Brendan Rodgers looks to add and improve the backline.
However, the higher valuation of €4 million from Besiktas for the 32-year-old may put an end to Celtic’s interest as they may not want to spend so much on an older defender having just signed a similar player in Compper.