Deco is close to completing his return to Brazil, with Fluminense revealing they have already agreed terms with the Chelsea midfielder.
The 32-year-old revealed several months ago that he was seeking a move back to the country of his birth, after spending 13 years in Europe.
Portugal international Deco, who joined Chelsea from Barcelona in 2008 on a three-year contract, now appears to have been granted his wish if he can negotiate his release from the Barclays Premier League club.
"As Deco himself said, the deal is well under way," said Celso Barros, the president of the group which owns Fluminense, a club based in Rio de Janeiro.
"It depends only on him being released by Chelsea and passing the medical tests, because the salary and length of contract have already been agreed.
"We will not talk this Wednesday, but in principle Deco will go to London to try to expedite his release with Chelsea. That done, he has asked Fluminense for at least a week to be with his children in Brazil and then he will report for medical tests and to start training."