Chelsea reportedly remain interested in signing Bayern Munich defender Niklas Sule on a free transfer.
Although the Blues are well stocked for options at the back, several of their players currently have less than six months remaining on their contract.
Antonio Rudiger, Cesar Azpilicueta and Andreas Christensen can all hold discussions with foreign clubs, but Chelsea are seemingly attempting to use the same option to find at least one replacement.
According to Sport1, the European champions have been in regular dialogue with the representatives of Germany international Sule.
Despite making 25 appearances for Bayern during the current campaign, the 26-year-old is currently insisting on taking on a new challenge when his deal expires at the end of the season.
Chelsea head coach Thomas Tuchel is said to be an admirer of the player, but the Premier League giants are said to face competition from Barcelona and Newcastle United.