The race for FC Basle defender Fabian Schar has intensified this week.
The London Evening Standard says Chelsea have joined the hunt for Schar, who has also been linked with Arsenal, Tottenham, Borussia Dortmund, Inter Milan and Napoli.
Schar impressed against Chelsea in the Champions League group stages this term, helping his side record shock victories home and away over the Blues.
The Switzerland centre half's current deal expires in the summer of 2015, although Basle do have an option to extend it by another year.