Chelsea hope to wrap up the signing of Atletico Madrid striker Diego Costa by Wednesday.
The Brazil-born striker has passed his medical and agreed terms with Chelsea and now all that is left is to dot the i's and cross the t's.
A source told PA Sport: "Chelsea have made an offer to Atletico Madrid in compliance with the buyout terms in Diego Costa's contract, and have been advised that the player has provided notice to Atletico Madrid invoking the buyout clause and directing the club to accept Chelsea's offer.
"Chelsea look forward to entering into formal transfer documentation with Atletico Madrid as soon as possible so that the player can concentrate on the World Cup."
