Bayern Munich must wait to be confirmed as Bundesliga champions for the ninth season in a row after they suffered a surprise defeat at Mainz.
The league leaders need just one win from their remaining three games to seal the title.
However, they fell behind early on when Jonathan Burkardt’s 18-yard strike beat Germany keeper Manuel Neuer.
Robin Quaison’s header made it 2-0 before fit-again Robert Lewandowski got one back in the 90th minute.