The Brazilian former World Player of the Year, who otherwise gave another pedestrian display, curled in an exquisite effort from around 30 metres in first-half stoppage time to bring Mineiro level at 2-2 against the Asian champions.
But with three minutes to go, Ronaldinho was fouled and was sent off for kicking out at an opponent in retaliation. Despite being reduced to 10 men, Brazil's Mineiro won the game with an injury-time goal from Luan.
Diego Tardelli had given Mineiro a second-minute lead before Muriqui equalised and Dario Conca put the Chinese club ahead with a penalty.
The South American champions had suffered a shock 3-1 defeat to Raja Casablanca in their semi-final on Tuesday, when Ronaldinho scored their only goal with another free kick in a similarly lacklustre display.