0:56

Dortmund keeper's 'horrible mistake' leads to Mainz's second goal

1:57

Mainz vs. Borussia Dortmund - Game Highlights

0:35

Felix Nmecha makes a great save

0:31

Alexander Meyer makes a great save

0:39

Lee Jae-Sung slots in the goal for Mainz

0:58

Leandro Barreiro finds the back of the net for Mainz