— Borussia (@borussia) July 21, 2020
However, a broken leg kept the Austrian out of action until December and he struggled for game time after returning.
Wolf made only five Bundesliga appearances this season, all late cameos off the bench.
The talented attacking all-rounder is now reuniting with former Salzburg coach Marco Rose at Gladbach.
If Die Fohlen are satisified with his performances next season, they will have the option to make the deal permanent.