The former Barcelona and AC Milan player sealed a surprise move to the Belo Horizonte club and is eager to make his debut for the Alvinegro as soon as possible.
The former Barcelona star failed to impress at Flamengo and suffered an acrimonious exit from the Rio de Janeiro giant after cancelling his contract due to a dispute over unpaid wages.
However, he declared himself eager to return to action as soon as possible.
"I'm very motivated, if all goes well and the coach feels that I can play, I want to be available soon," Ronaldinho stated in a press conference.
"I am physically well and until the end of last week I was playing, I'm fine. I will do my best to fight for titles and ensure positions in major competitions for Atletico. I have the opportunity to play at a club with great fans and it motivates me to do my best."
Galo were keen on a big-name signing having failed to agree terms with Diego Forlan and Ronaldinho could now make his debut against Bahia on Wednesday.
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