The former Barcelona and AC Milan star was delighted to have joined a prestigious group of players to win both the Copa Libertadores and Champions League
Mineiro were beaten 2-0 in the first leg of the final in Paraguay but turned things around in the return as goals from Jo and Leonardo Silva levelled the tie before the Brazilians ultimately triumphed on penalties.
"This is the reason why I returned to Brazil. This is the one trophy that was still missing," Ronaldinho was quoted as saying by Reuters.
"Everyone said that I was finished and that my time was over. Let them talk now..."
Wednesday's victory saw Ronaldinho join an elite group consisting of Cafu, Roque Junior, Dida, Carlos Tevez, Walter Samuel and Pablo Sorin to have lifted both the Champions League and Copa Libertadores trophies.
The 33-year-old won European club football's elite competition with Barcelona in 2005-06.