Shinji Okazaki got one over his former club with a goal on his Mainz debut, helping to defeat Stuttgart this afternoon.
Nicolai Muller put Mainz in front in the 14th minute, but Vedad Ibisevic replied within two minutes for the guests.
Okazaki then equalled his tally for the whole of last season as a Stuttgart player to put Mainz in front again before Muller got his second of the game.
Martin Harnik reduced the arrears once more, but it was too late for Bruno Labbadia's men to find an equaliser.
Mainz forward Nicolai Muller, who earned his first Germany cap in June, pounced on two mistakes by Stuttgart defenders Gotoku Sakai and Benedikt Rocker on his way to giving the home side the lead.
The celebrations had not yet subsided when Ibisevic brought Stuttgart level, meeting Ibrahima Traore's low cross at the near post to beat Heinz Muller.
Okazaki spurned a good chance to open his Mainz account before the break, but he made amends after the interval to give the hosts the lead soon after two Zdenek Pospech shots were saved by Sven Ulreich.
The Japan international received the ball inside the penalty area with his back to goal, and he turned in an instant to sweep a shot inside Ulreich's post.
Mainz goalkeeper Heinz Muller denied Konstantin Rausch with two excellent fingertip saves before Nicolai Muller doubled the home team's advantage, wriggling free of his marker before shooting low past Ulreich, who got a hand to the ball.
Cacau was sent on by Labbadia as Stuttgart gambled, and his shot was fumbled by Heinz Muller to Harnik to pull another one back, but the visitors could not find the route to goal again as Mainz held on.