The Australian goalkeeper had little to do and had no chance with either goal, beaten by a deflection and sold short by a Sahin mistake.
Continued his good form in Schmelzer's absence. Solid in defence and showed his ability to beat players and deliver good crosses when pressing on.
In the right time at the right time to deflect Jojic's early strike beyond Karius, despite the ball appearing to strike his hand.
Flicked on a Reus free-kick to put Dortmund 3-2 ahead and provided a couple of good crosses from the right hand side.
Another steady outing from the Greek defender, who wasn't tested all too often by the runs of Okazaki.
A threat from set pieces in the opposition penalty area and perhaps had a headed effort bounce over the line. Made a number of well-timed challenges.
Fortunate in front of goal once again, as the Serbian midfielder's effort deflected off Kirch and into the back of the net. An early yellow card prevented him from providing his usual edge and intensity.
Central to everything good about Dortmund yet again. Provided countless dangerous set piece deliveries and converted a brilliant penalty to wrap up the win.
Provided the assist for Lewandowski's goal, squaring for his teammate to have an easy finish. Good movement but caught offside a few times.
Made an awful mistake for Mainz's second goal, playing a backpass straight to Okazaki, who made no mistake. However, his pass through to Mkhitaryan in the build up to Lewandowski's goal was exquisite and he broke up play well.
Powerful and clinical performance from the Poland international and Noveski struggled to deal with him. Converted his goal with ease and had another denied by the arm of Bungert.
Made a few impressive close-range saves, but didn't command his area well whatsoever, failing to deal with Reus' free-kick deliveries.
Substituted at the break after failing to offer much going forward for the visitors, despite being somewhat out of position.
Battled with Lewandowski all game and was fortunate to not concede a penalty for trying to haul the Dortmund man to the ground in the area.
Shown a straight red card somewhat harshly for blocking a Lewandowski's shot with his arm, despite the German defender being unable to do much else to avoid doing so.
Covered at the back post quite well at times, but didn't look entirely comfortable in a position he doesn't play all too often.
The experienced defender didn't have to deal with Jojic's running down the right hand side too often, as most of Dortmund's creativity came through Reus in the centre.
Had a couple of half chances from range, but failed to really impose himself or act as the link between midfield and Okazaki.
A very poor performance in the first half, giving the ball away needlessly in the build up to Lewandowski's goal. Substituted at half-time in a game to forget.
Another steady game from the former Furth midfielder, breaking up play fairly well and not looking out of his depth.
Grabbed two goals for his side in rather fortunate circumstances. His first strike was deflected over Langerak by the boot of Hummels, before Sahin gifted the Japan international possession inside the penalty area for his second.
A quiet game from the Cameroon international, who tried to drive at Piszczek whenever possible but didn't have much luck. Nodded wide at the back post from a Bell cross, where he should have done much better.
The 21-year-old managed to get even more minutes off the bench, making less glaring errors than the man he replaced, but similarly failed to aid offensively.
His positive running caused Dortmund a few problems in the opening ten minutes of the second half, but the 21-year-old faded from the game afterwards.