Chelsea will reportedly demand AC Milan midfielder Kaka or Barcelona forward Lionel Messi as a direct summer replacement for Didier Drogba.

Blues boss Avram Grant and the Stamford Bridge hierarchy have run out of patience with the unsettled Ivory Coast international's public posturing over his future, according to the Daily Mirror.

Chelsea feel that Barcelona and AC Milan are the two most likely suitors for the former Marseille striker, who has spoken of his desire to join either club.

Drogba is valued at £40million by Chelsea and any possible swap deal would illustrate the club's determination to drive the hardest possible bargain.

Kaka and Messi represent the "fantasy" footballers that Roman Abramovich wants to bring to Stamford Bridge.

Over the last two summers AC Milan have resisted Real Madrid's attempts to snap up Kaka, however their signing of Brazilian boy wonder Pato could open the door to a potential deal.

Barcelona president Joan Laporta, however, would be more reluctant to let Messi leave the Nou Camp.