The Brazilian arrived at Stamford Bridge from Internacional in 2012 and went on to make 203 appearances for the club, scoring 61 goals and providing a whopping 110 assists in that time.
He also won the Premier League twice with the Blues, in 2015 and 2017 respectively, lifted the Europa League in his first season and also won the League Cup in 2015.
But after falling out of favour at the Bridge, Oscar made no secret of wanting to move elsewhere with money and security for his family firmly on his mind.
As a result, he went on to shock the football world and sign a £400,000-a-week contract with Chinese Super League side Shanghai Port FC in a £60million move in the January transfer window of the 2016/17 season.
That was despite him having interest from Juventus, Inter Milan, AC Milan and Atletico Madrid and being at the peak of his career at the age of 25.
READ MORE ON CHELSEA
'My starboy' - Chelsea fans compare Mudryk to Arsenal's Saka with bizarre goal statistic
Chelsea fans told to keep an eye on academy star after 'charged up' debut
Now, though, the midfielder reportedly earns £20.8m a year.
In December 2019, he extended his deal by five years just before the league rules changed, with foreign players now only able to earn £2.7m a year since 2020.
That means Oscar has earned a eye-watering £146.2m in wages alone.
In the meantime, he's won two league titles, the most recent one being last season.
Most read in Football
Roberto Firmino faces uncertain Saudi future amid Premier League interest
Arsenal told to be ruthless and sell academy star to fund Premier League title bid
How will the Africa Cup of Nations affect the Premier League this season?
Hodgson gives prickly interview as Palace boss asked about body language and relegation
He's also now surpassed the number of appearances he made for Chelsea, playing 208 games for Shanghai.
What's even more jaw-dropping is he's still only 32, meaning he has plenty of fuel left in the tank to earn himself more dough and carry on his career.
And earlier this year, he admitted to talkSPORT that it would be a 'dream' to return to Chelsea.