The victory crowned the club's farewell to Ronaldo, who retired last Monday, after he had completed a lap of honour accompanied by his two sons to applause from both sets of fans.
In honour of the holder of a record 15 World Cup goals, all the Corinthians players wore a number nine on the back of their shirts, such as goalkeeper Julio Cesar with a 19 and midfielder Paulinho 89, and the nickname "Fenomeno".
"I wanted to thank you for every minute I was here, each of your shouts and applause, you who always supported me during my time at Corinthians," Ronaldo told the crowd.
"I wanted to thank you for the unique experience of knowing Corinthians and their fans," he said after being presented with a plaque by the club's president.
Brazilian-born Portugal striker Liedson, signed to fill the void left by the three times FIFA Player of the Year, scored the best of the goals to seal the victory three minutes from time with a lob over Santos keeper Rafael.
Left-back Fabio Santos, who has replaced the departed Roberto Carlos, scored the first two goals with a free-kick and a penalty. Brazil midfielder Elano pulled one back for Santos.
Ronaldinho, who followed Ronaldo back home to Brazil to play for Flamengo, also had a Sunday to celebrate in the Carioca (Rio de Janeiro) championship.
Although Ronaldinho had a quiet game, Flamengo qualified for the final of the first phase of the competition by beating Botafogo 3-1 on penalties following a 1-1 draw at the Enganhao stadium.
Flamengo will meet surprise finalists Boavista, who upset Brazilian champions Fluminense 4-2 on penalties after a 2-2 draw in the other semi-final.
"It's marvelous in such a short time to reach a final already," Ronaldinho said. "I hope to reach it in good form and have a good match."
