The hosts currently sit 12th in the Bundesliga, with just one win from their last eight league matches, while Dortmund occupy third spot, and Klopp predicts Bremen will be hungrier than ever to record three points.
"I just read a little bit about Bremen but obviously they are not satisfied with their first two matches this year," he told reporters. "They want to give all they have against us.
"They want to have a fight with us - that’s what Bremen made pretty clear the way they talked about Saturday. But we have our aims and we will fight for them as well.
"And one thing is for sure - without winning duels this match is not going to be won. But we have the abilities to cause Werder Bremen problems they cannot solve by just fighting. And that’s what we want to do."
Dortmund's form has been some way short of that which saw them reach the final of last season's Champions League - partly due to injuries across the squad - and Klopp feels that has had an effect on how their opponents approach matches.
"A lot of people spoke very well about us in the last couple of years," the coach added. "And of course every team deals with it in a different way.
"I guess a lot of players from other teams watched some matches where we were involved and thought, 'Well, that is some nice football they play'.
"But still people had the idea that we are beatable. And we supported this idea in some matches in the last sixth months.
"We don’t have that kind of respect in the league that for example Bayern Munich has. No team soft-pedals against us. That is a fact. You have to work for respect and we will continue our way, which was never easy. That’s the way it is."