Bochum s Jordi Osei-Tutu, centre, shoots on goal,during the German Bundesliga soccer match between VfL Bochum and 1. FC Union Berlin in Bochum, Germany, Sunday, Oct 23, 2022. AP
Union came into the weekend with a four-point lead, but the gap was cut to just one after Bayern Munich defeated Hoffenheim 2-0 on Saturday.
Bochum took the lead in the final minute of the first half when Philipp Hofmann headed in a corner.
Looking to ignite a tired-looking side exhausted by frequent midweek matches as a result of their first Europa League campaign, coach Urs Fischer made three changes in the 63rd minute.
However it was the home side which continued to look fresher, scoring a second on the counter in the 71st minute when Christopher Antwi-Adjei crossed for Gerrit Holtmann to score.
Union had a chance to mount a comeback when awarded a penalty in the 77th minute, but Bochum goalkeeper Manuel Riemann saved Milos Pantovic's tentative spot-kick.
Pantovic got on the board in the last minute of injury time, but it was not enough as Union failed to secure three points for just the fourth time this season.
The win was just Bochum's second of the season, lifting them from last spot in the table ahead of Schalke.
Schalke have a chance lifting themselves off the foot of the ladder when they take on Hertha in Berlin in Sunday's late game.
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