Bayern Munich entered Wednesday's clash with Mainz as overwhelming favorites. The Bavarian giants had been beaten just once all season in the Bundesliga, and they had a perfect record of 11 wins in as many games at home.
During Pep Guardiola's time as head coach, they had lost just three games at the Allianz Arena in league play, an absolutely outstanding record.
Yet Mainz did what so many before them had failed to do: They not only took points from Bayern at the Allianz, they went ahead and then scored the winner after conceding an equalizer.
It was an improbable result that, coupled with Borussia Dortmund's 2-0 win against Darmstadt, saw Bayern's lead over BVB cut to five points.