Tuchel said that, although any result would be a bonus, his side would have a complete gameplan about how best to limit the threat of Pep Guardiola's men.
"I think Bayern took their game up to a new level at Manchester City in the Champions League and against Bayer Leverkusen," Bundesliga.com quotes Tuchel as saying. "[It could be] a very lopsided contest.
"However, we won't be giving them anything for free. [I will give my tactical instructionss] very late on, maybe on Friday evening or Saturday morning. It'll be made-to-measure, and be far removed from a home game against Eintracht Braunschweig."
Tuchel has been in charge at Mainz since 2009.