Atletico Madrid striker Diego Costa has completed his transfer to Chelsea on a five-year deal.
The fee for the 25-year-old Spain international is understood to be £32m.
“I am very happy to sign for Chelsea,” Costa said. “Everybody knows it is a big club in a very competitive league, and I am very excited to get started in England.”
Costa becomes Chelsea’s third summer signing following the arrivals of Cesc Fabregas and Mario Pasalic.
The striker scored 36 goals in 52 games for Atletico last term as they won their first La Liga title since 1996 and reached theChampions League final.
Chelsea boss Jose Mourinho had made the addition of a “killer” striker a key priority during the summer.