The free-kick specialist insists that his compatriot still has what it takes to play at the top level and backs him to follow in the footsteps of David Beckham by retiring at PSG
PSG signed the England legend in January 2013 before he subsequently retired from football in May after helping the capital club to deliver the Ligue 1 title.
The 33-year-old Ronaldinho played for the club from 2001 to 2003 and recently revealed that he could envision himself returning to Parc des Princes to bring the curtain down on his stellar playing career.
And Juninho believes that Ronaldinho is in superior condition than Beckham was last year at the time of his signing but warns that the French club may find it hard to fit his compatriot into a competitive squad.
"I think that Ronaldinho is in much better shape than Beckham was when he signed for PSG last season," he said to RMC.
"I saw him play in the Brazilian league and the Copa Libertadores. In some matches, you still can see the real Ronaldinho but I do not know how PSG would respond because they have a full complement [of players] and are candidates for the Champions League."
Ronaldinho has not been called up to the Brazil squad since April but Juninho feels that he could still do a job for the Selecao, even if he may not recapture the magic of his Barcelona heyday.
"He will never regain the level of Barcelona but he still brings a lot of things," the Vasco da Gama star continued.
"He will be back soon. Ronaldinho, even at his age, has time to offer something. He scores goals, he makes assists, he's smart and, above all, on the ground no one can be him.
"This is Ronaldinho. He comes with a personality and he still has that light on him."