Tuchel is aware that against a team such as Dortmund, who have a number of set piece specialists, his side cannot concede too many fouls around the penalty area.
"We've had a tendency of committing too many fouls in our last few games," he told Bundesliga.com. "That's an issue. We don't know exactly how we'll eradicate it because plenty of the fouls come from just being over-zealous. We train very actively in tackling so it's a fine line.
"Of course it's a blow to Dortmund to have Manuel Friedrich playing with such little match practice instead of somebody like Mats Hummels or Neven Subotic, but he can play long balls to Robert Lewandowski, who can hold the ball up well. So it actually doesn't help us in the slightest that he hasn't played for the past four months."
Mainz have won three of their last four games in the Bundesliga.