Chelsea have announced Jorginho as their first summer signing, just hours after Maurizio Sarri was confirmed as manager.
Jorginho joins Sarri in arriving from Napoli after a fee worth up to £57.4 million was agreed with the Italian side, a figure which is understood to include a payment for the coach.
The Italy international has signed a five-year contract and will wear the no.5 shirt.
Jorginho said: "I am absolutely ecstatic to be here at Chelsea. It is not easy to become part of such a big team so I am very, very happy.
"I am excited to play in such an intense league, for a team that gives everything to play and win."
The midfielder was expected to join Manchester City, with the Premier League champions having reportedly agreed a fee in June, but the late U-turn has seen Chelsea seal his signature.
Club director Marina Granovskaia said: "We are delighted Jorginho has chosen to join Chelsea. He was one of the most coveted midfielders in Europe and will become an important member of the playing squad.
"He has demonstrated his quality working under Maurizio Sarri and we are convinced his signing will help bring further success to Stamford Bridge."
Jorginho is the second midfielder City have missed out after always seeing Fred join rivals Manchester United.
