Sunderland boss Roy Keane is reportedly lining up a swoop for former Celtic team-mate Bobo Balde.
Celtic will reportedly be willing to sell Balde, given that they are pretty well stocked at centre-half, with Stephen Pressley, Stephen McManus, Gary Caldwell, Darren O'Dea and the returning John Kennedy all competing for two places.
However, Balde is understood to be keen on staying at Celtic Park, where he still has two years remaining on his contract.
Both Newcastle and Blackburn made enquiries about Balde last summer, but were told the big centre-half did not want to move away from Glasgow.