They have agreed a deal to sign Palmeiras gem Estevao Willian, who will join the London club next summer when he reaches the age of majority.
"Chelsea Football Club has agreed a deal to sign teenage forward Estevao Willian from Palmeiras, with the Brazilian to officially join Chelsea next summer," the Chelsea statement said.
"The 17-year-old has already built a strong reputation in South America as one of the most exciting talents around due to his skilful dribbling and electric pace, causing defences plenty of problems in his breakout season in senior football," added the statement.
The young player has made 10 appearances in the Brazilian league for Palmeiras, contributing two goals and two assists, as well as scoring in the Copa Libertadores and Copa do Brasil.