Bayern Munich have admitted Jerome Boateng is not unsellable and say the club will listen to important offers for the Germany international.
Manchester United have shown interest in the former Manchester City defender but believed Bayern would be unwilling to let him leave the Allianz Arena.
The Red Devils are keen on signing Tottenham star Toby Alderweireld but have been put off by Spurs £75m valuation of the Belgian and Jose Mourinho is analysing other targets.
Boateng left City for Munich in 2011 but he recently admitted he would consider leaving the club and Karl-Heinz Rummenigge has revealed the German could leave the club.
If a club comes to us and he says that he wants to join that club, then we will negotiate, said Rummenigge.
But the offer has to be important
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Mourinho is prioritising the signing of a centre-back over a left-back and has around £60m to spend on a new defender.
United have signed Porto star Diogo Dalot and have agreed a deal to sign Shakhtar Donetsk ace Fred.