The Brazilian playmaker returns to Germany with Diego Simeone's side to take on former club Werder Bremen's rivals in Europe's secondary competition
The Brazilian played for Hannover's rivals Werder Bremen between 2006 and 2009 and scored 38 goals in 84 league appearances for the Bundesliga outfit.
"I never worry about that, I am used to it," Diego told AS, referring to the jeers he is likely to receive at Hannover.
"This is not the first nor the last time I will go through this. I respect Hannover, the players and the fans, but when the game starts, I will give everything for my team to win."
Diego Simeone's side go to Germany with a slender 2-1 lead from the first leg, but face a stiff test at the AWD Arena, where Hannover are unbeaten in the league and in Europe this season.
And Diego cautioned his team-mates against taking the threat of their opponents lightly.
"We must be careful," he warned. "They are compact, patient and organised in defence.
"They always wait for the right time to do damage and have very fast players."
The second leg kicks off at 21.05CET on Thursday.