Listless Borussia Dortmund handed 3-0 defeat by Mainz 05
Edin Terzic made a triple change at half-time to try and remedy the situation, with Jadon Sancho, Ian Maatsen and Julian Brandt coming on. Borussia Dortmund upped the ante after the break, and Youssoufa Moukoko had a goal ruled out for the narrowest of offside calls.
Borussia Dortmund struggled to create any clear-cut chances other than that despite pushing for a way back into the game, and Mainz managed to hold on for the three points quite comfortably in the end.
The win is a huge boost to Mainz's hopes of avoiding relegation. They now find themselves two points clear of 16th placed Union Berlin ahead of the final matchday of the season.
Borussia Dortmund, meanwhile, are now guaranteed to finish fifth in the Bundesliga. While that will be enough for a place in next year's Champions League, there will no doubt be disappointment in the BVB ranks over the way they have performed in the league this season.