Mainz fought back from a two-goal deficit to snatch a 3-3 draw five minutes from time at defending champions Wolfsburg.
Obafemi Martins scored in the seventh and 20th minutes to give Wolfsburg a 2-0 lead but Chadli Amri struck in the 35th minute and Andreas Ivanschitz made it 2-2 shortly before the interval.
Zvjezdan Misimovic gave Wolfsburg the lead again after 64 minutes but Tim Hoogland equalised again for the promoted side Mainz in the 85th minute.
Wolfsburg jumped ahead after just seven minutes after a finely played high ball into the box saw Martins head home past Mainz goalkeeper Heinz Muller from four yards.
Mainz had the ball in the net seven minutes later but Amri was ruled offside.
Wolfsburg doubled the lead after 20 minutes as Edin Dzeko fed a through ball to Martins, who rounded Muller and slotted home.
The visitors pulled a goal back 15 minutes later as Amri played a high ball from Ivanschitz with his chest and head before volleying into the corner.
And the game was level four minutes from the break on Ivanschitz's curling free-kick from 20 yards into the upper right corner.
Wolfsburg regained the lead after 64 minutes as Marcel Schfer played a high ball to the far right post where Sascha Riether headed back into the middle where Misimovic blasted home from six yards.
Mainz had another goal ruled out for offside with 11 minutes left but eventually grabbed the equaliser with five minutes left.
Aristide Bance crossed to the far post to Hoogland, who chipped back across Wolfsburg keeper Diego Benaglio and into the net.