Freiburg need "a special day" on Thursday to overcome French side Lens and reach the Europa League last 16, coach Christian Streich has said.
The first leg play-off match in Lens ended 0-0 last week, and Streich said on Wednesday that an all-out effort will be needed in the return leg at home.
"There is a chance for us. We have to reach the maximum of our capabilities and the capacity for suffering," Streich said, because only then you can "beat such teams on a special day."
Freiburg have not won in five games in all competitions but came from behind three times on Sunday to draw 3-3 with Eintracht Frankfurt on Sunday in the Bundesliga.
Forward Vincenzo Grifo said this fightback showed the good morale of the team.
If Freiburg progress it could help Germany get a fifth Champions League slot and another European berth in general but Streich said that advancing "is enough motivation."
In team news, defender Matthias Ginter could return into the squad from Achilles tendon problems while Streich said that Yannik Keitel is unlikely to feature owing to back and calf problems.