Hamburg  - Bayern Munich remain without a win in the new Bundesliga season after goals Saturday from Andreas Ivanschitz and Aristide Bance helped newly-promoted Mainz 05 to a shock 2-1 victory.

Bayer Leverkusen continued their strong start to the season and go top on goal difference courtesy of a 5-0 drubbing of SC Freiburg while Borussia Dortmund and VfB Stuttgart both lost ground after playing out a 1-1 draw.

Leverkusen now have seven points from three games, level with Schalke 04, who dropped their first points of the season when they were held to a goalless draw Friday at Hoffenheim.

Champions VfL Wolfsburg sit third on six points ahead of their visit to SV Hamburg on Sunday while Munich languish in 12th on just two points.

Mainz were every bit Bayern's equals in the early stages and took a deserved lead on 25 minutes when Austrian Ivanschitz sent in a shot from 25 metres that slipped its way in under Bayern goalkeeper Michael Rensing's outstretched arm.

Things got even worse for Louis van Gaal's side seven minutes before the break when Bance rose above Daniel van Buyten to head home from 10 metres and make it 2-0 to the Thomas Tuchel's side.

With Bayern now looking to pull back a two-goal deficit, Van Gaal immediately brought on Croatian striker Ivica Olic for midfielder Danijel Pranijic.

Mainz gave Bayern a lifeline on 47 minutes when Nikolce Noveski headed a Thomas Mueller cross into his own net.

Mueller had a glorious opportunity to equalize on the hour-mark but headed Van Buyten's pinpoint cross wide.

Van Gaal brought on Jose Sosa for Miroslav Klose with 18 minutes left as Bayern continued to press for an equalizer but the Argentine sent a free-kick opportunity over the bar four minutes later.

Mario Gomez hit the side-netting as Bayern got ever more desperate but Mainz held on for a stunning win to move up to fourth on five points, level with Eintracht Frankfurt, who drew 0-0 with Cologne.

While Bayern struggled, Leverkusen put in the performance of the day with a 5-0 demolition of newly-promoted Freiburg.

Stefan Kiessling netted his third goal of the season on 35 minutes to open the scoring at Freiburg's Badenova stadium, firing home after being found by Simon Rolfes.

Swiss international Tranquillo Barnetta doubled Leverkusen's lead two minutes after the restart with a sweetly-struck shot from the edge of the area while a further brace from Eren Deriyok, sandwiched by Barnetta's second, completed the rout.

Stuttgart lost ground despite coming from a goal down at Borussia Dortmund to salvage a 1-1 draw.

Nelson Valdez put Dortmund ahead on 27 minutes, Nuri Sahin setting the Paraguayan up to finish clinically, placing the ball beyond the reach of Jens Lehmann.

Julian Schieber could have drawn Stuttgart level on the stroke of half-time after playing a combination with Cacau but Dortmund goalkeeper Roman Weidenfeller saved the 20-year-old's shot well.

Dortmund paid the price almost immediately after the restart as Georg Niedermeier headed in from five metres.

In the day's other game, Jiri Stajner scored twice and could also afford to miss a penalty as Hanover 96 beat Nuremberg 2-0.

In Sunday action, apart from Hamburg's clash with Wolfsburg, Werder Bremen entertain Borussia Moenchengladbach while VfL Bochum face Hertha Berlin.  (dpa)