Oscar has signed a new contract with runaway Premier League leaders Chelsea.
The Brazilian international will now remain at Stamford Bridge until the summer of 2019.
The 23-year-old midfielder has made 15 appearances this season in all competitions, scoring four goals for the Blues who are currently unbeaten and four points clear at the top of the Premier League table .
Oscar told the club's website: "I am so happy because I love playing for Chelsea and living in England. I have enjoyed playing here for two years, and now I have five more, so I am very happy."
The Brazilian joined Chelsea from Internacional in the summer of 2012 and has been a vital member of the first-team since, scoring 11 goals last season.
The second of two goals he scored on his first start for the club, in a Champions League game against Juventus, earned him the club's Goal of the Season award, and he ended his first season as a Chelsea player with a Europa League winners' medal.
Oscar has also amassed 40 caps for Brazil since making his debut against Argentina in 2011 and has scored 11 times, including the only goal in the 7-1 humbling by Germany in last summer's World Cup semi-final.