Chelsea have secured their second signing of the summer transfer window after Diego Costa put pen to paper in a five-year deal to complete his move from Atletico Madrid.
Earlier this month, the Blues announced that a fee - believed to be £32m - has already been agreed with the La Liga champions for the Brazil-born Spanish striker.
A statement on Chelsea's official website read, "Chelsea Football Club is delighted to announce Diego Costa has today completed his transfer from Atletico Madrid by signing a five-year contract."
"He will join up with the first team for our pre-season European training camp next week."
The 25-year-old is the second Spanish international to become a part of Jose Mourinho's side this summer following Cesch Fabregas' arrival from Barcelona. Costa arrives at Stamford Bridge after a stellar season in Spain and a lacklustre performance at the World Cup for Vicente Del Bosque's side in Brazil.
However, the former Real Valladolid player expressed delight at signing for the West London club.
He said, "I am very happy to sign for Chelsea. Everybody knows it is a big club in a very competitive league, and I am very excited to get started in England with a fantastic coach and team-mates."
"Having played against Chelsea last season I know the high quality of the squad I am joining."
"I would like to thank everybody at Atletico who made me into the player I am, it was an incredible time for me, but now I am starting a new adventure and I hope to win many trophies with Chelsea."
Costa arrives in the Premier League having scored 36 goals in all competitions for Diego Simeone's side last season, helping them reach the Champions League final. His 27 goals in La Liga helped Atletico win the title for the first time since 1996.