The Dutchman has made it clear that the Gelsenkirchen side are aiming for victory in Tuesday's Champions League encounter with Montpellier in order to seal top spot
The Bundesliga side currently lead their pool with 11 points from five games, and a win against the Ligue 1 champions in France on matchday 6 would confirm top spot.
"My priority is to keep the lead in this group. In the knock-out round there are no weak teams, but by finishing first we might avoid some of the bigger ones," the Dutchman said at a press conference.
"We are here to win the game and the group. Things would be a bit different if we had to win to qualify, so I think that we will be a little bit more relaxed but still focused.
"Montpellier play good football. French football is usually quite skillful. Montpellier have less experience than the other teams in this group, but they showed in our first meeting that they are a quality team."
Tuesday's encounter is scheduled to kick off at 20:45CET.