Chelsea have opened talks with Besitkas over the sale of Senegalese striker Demba Ba in order to free up room to pursue a move for Napoli forward Jose Callejon, according to the Evening Standard.
Ba found first-team opportunities difficult to come by under Jose Mourinho at Stamford Bridge, appearing in only 50% of Chelsea's Premier League fixtures, and Besiktas are among a group of three Turkish clubs who want to offer the forward a summer escape.
The 29-year-old is expected to swap West London for Turkey and Mourinho is already thinking of a forward line which could include Eden Hazard, Diego Costa and Callejon, who the Blues want to lure from Serie A in a mega-money summer switch.
Callejon impressed this season in his first campaign with Napoli, scoring 15 times in Serie A and proving to be the kind of creative, versatile attacking option that Mourinho craves.
Persuading Napoli to let the Spanish star swap Naples for the Kings Road could be very tricky though, as former Chelsea boss Rafael Benitez is desperate to build a side capable of overthrowing Serie A kings Juventus around Callejon and Gonzalo Higuain.
Mourinho has the funds to chase Callejon though after agreeing to let David Luiz join Paris Saint-Germain in a blockbuster £48m deal, money he plans to spend on turning Chelsea into a genuine attacking force next season.
To make that happen Ba has been deemed surplus to requirements, which with Samuel Eto'o also leaving Chelsea could make Fernando Torres the only recognised striker on Chelsea's books before what promises to be a busy summer of spending for Blues owner Roman Abramovich.