Chelsea have signed midfielder Nemanja Matic from MFK Kosice, according to the Slovakian club.
The 20-year-old, who has played youth football for Serbia, completed a switch to Stamford Bridge for 1.75 million euros (£1.5million) on Monday, read a statement on the club's official website.
MSK president Blazej Podolak said: "At around five o'clock in the evening we signed the contract on the transfer. Matic goes for 1.75 million euros.
"The success was down to the the fact that the money does not come in instalments, but immediately."