The Bundesliga clash was already eventful enough with ongoing protests aimed towards the league's hierarchy for playing the match on a Monday, and a VAR incident which plunged the match into disarray.
But the battle at the bottom took another downward turn for visitors Freiburg - and Schwolow in particular.
Pablo de Blasis had already beaten the German goalkeeper with a penalty in the seventh minute of first-half injury-time, following a lengthy VAR debate, before the Argentine was gifted his second goal in the 78th minute.
Schwolow lazily attempted to pass the ball out to a team-mate despite being chased down by Robin Quaison. The Swedish forward intercepted the loose pass and squared to De Blasis to apply a simple finish (which he did his best to mess up, admittedly).
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And we all thought Joe Hart had a difficult Monday night...
Mainz's 2-0 win was their first home victory since January 20, and means they've now switched league positions with Freiburg. Die Breisgauer have dropped into the relegation play-off spot - 16th - due to their inferior goal difference.
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Best celebration ever? Romanian striker scores, applauds his own goal from the stands
