Brazillian, Oscar has left Chelsea to join Chinese side Shanghai SIPG for £52m record fee.
The 25-year-old has been frozen out of the Blues first team under Antonio Conte – and has finally moved on.
Oscar won the Premier League title under Jose Mourinho in 2014-15 and the Europa League in 2012-13 during his four and a half years at Stamford Bridge.
A club statement said: “Chelsea Football Club and Shanghai SIPG have agreed terms for the permanent transfer of Oscar.
The 25-year-old will join the Chinese Super League team at the beginning of the January transfer window.
“He has been a Chelsea player for four-and-a-half years, helping us lift the Premier League, League Cup and Europa League as well as scooping two Chelsea Goal of the Season awards after stunning strikes against Juventus in 2012, on his full debut, and QPR in 2014.
“Skilful and tenacious, Oscar has been highly regarded by fans, players and staff during his time as a Blue, scoring 38 times from 203 Chelsea appearances.