The Rossoneri are now in third place after victory at Lazio on Sunday.
“Leonardo has been very good at finding this formula with three strikers and a playmaker, and putting many talented men together who sacrifice themselves for the group," said Ronaldinho.
“Watch out because we can still improve. I say that Milan will go far."
Fellow Brazilian Thiago Silva heaped praise on Ronaldinho for the assist that allowed him to score Milan's opening goal.
“When Dinho presents you with balls like these, you cannot do anything but put them away,” Silva joked. “In the second half, Lazio frightened us a little. We had in our heads the experience with Napoli.
“Now we are thinking about giving another acceleration after the international break.”