Sao Paulo and Argentina's Tigre play the second leg of the tournament's final on Wednesday night after a 0-0 draw in the first leg in Argentina.
With away goals not counting, any draw would take the match to penalties.
Lucas has already agreed a deal to join Paris St Germain in January after the French side paid 43million euros to take him away from the Morumbi stadium, where tomorrow's game will take place.
"Time is coming to an end," Lucas told reporters in Sao Paulo. "My heart is shocked, but I still have some training and a decisive game left.
"I really want to give Sao Paulo this title to give back all the love this club have given to me."
Without striker Luis Fabiano, who was sent off in the first leg, Lucas knows all eyes will be on him in the return game.
"I know everybody expects a lot from me, according to all I have experienced at this club so far," he added. "I am ready for that.
"With the help of the guys and supporters, who will fill the stadium, all the conditions are set to clinch the title."
Coach Ney Franco has confirmed Willian Jose will replace Fabiano.
Willian is Sao Paulo's top scorer in the Copa Sudamericana with three goals and Franco said: "He is emotionally prepared and he wants to play.
"I hope he and all the players have a happy night, playing well to clinch the title. Willian is showing confidence and he is ready for the game."
Tigre, meanwhile, will be without defender Alejandro Donatti, who was sent off at the same time as Fabiano in the first leg. Coach Nestor Gorosito has yet to name Donatti's replacement.
Fellow defender Mariano Echeverria knows Sao Paulo's players are much more experienced in continental finals but is hoping to spring a surprise.
"We level their experience with our heart," he told Argentinian newspaper Ole. "That is the extra thing we have. We'll try to ruin their celebration.
"A crowded Morumbi is the ideal environment. I like when everything is against me. Tigre players kill for their team-mates. Besides, they have the responsibility to win the title."