
Nils Petersen scored just 63 seconds after being introduced, damaging Borussia Monchengladbach's top-four hopes.
Borussia Monchengladbach's Champions League aspirations have been dealt a major blow after Freiburg inflicted a 1-0 defeat in the Bundesliga on Friday.
Gladbach were generally the livelier of the two sides in attack, but they failed to make the most of their chances and Freiburg snatched a hard-fought win, giving Bayer Leverkusen and RB Leipzig the advantage in the three-way battle for third and fourth.
Alexander Schwolow in the Freiburg goal was a frequent cause of frustration for Marco Rose's men, particularly in the first half, while Florian Neuhaus had a goal wiped out after straying offside.
