Bayern have already secured Group A top spot and their place in the knockout stage, having won all four group matches so far.
"The (4-0) win in Dortmund (on Nov. 4) was a key moment for us," Tuchel told a press conference. "For the way we won and the way we played over 90 minutes. It gave us a lot of confidence."
"You can see that in our game and I hope it remains like that and we can improve some things as well," he said.
Copenhagen are in second place on four points, ahead of Turkey's Galatasaray on goal difference. Manchester United are in last place on three and all three teams can still finish second in the group and advance.
"Copenhagen have put in a strong performance in the entire group stage so far. They have impressed in the group, which is no real surprise to us," Tuchel said.
"Even though there's a gap in the points their matches did not feel like that. They fought every match and we expect that tomorrow again."
The coach said the Dutch defender was unlikely to feature again this year.
"My feeling says no," Tuchel said.