Werder players, from left, Naldo, Per Mertesacker and Hugo Almeida celebrate a goal against Wolfsburg. (David Hecker/AFP/Getty Images)

Per Mertesacker scored in the second minute of injury time as Werder Bremen rallied for a 2-2 draw against defending champion Wolfsburg on Saturday in Frankfurt to return to the top of Germany's Bundesliga.

Bayer Leverkusen, which also has 27 points, can reclaim top spot Sunday when it plays Stuttgart.

Mertesacker's header from close range after a corner from Mesut Oezil stretched Werder's unbeaten run to 21 games in all competitions.

Edin Dzeko scored both goals for visiting Wolfsburg, which led twice.

Promoted Mainz came from behind to draw 1-1 at home against Hamburg, which is now winless in six games.

Three teams won on the road. Borussia Dortmund edged 10-man Hoffenheim 2-1, Freiburg won 1-0 over Nuremberg and Eintracht Frankfurt beat bottom-place Hertha Berlin 3-1.

Schalke plays Borussia Moenchengladbach later on Saturday. Bayern Munich plays Sunday in Hannover.

In Bremen, Dzeko opened the scoring after 42 minutes, shaking off defenders Naldo and Sebastian Boenisch before beating Werder goalkeeper Tim Wiese. Until then, Werder had dominated the first half.

Hugo Almeida levelled for Werder in the 63rd minute, blasting the ball home after Makoto Hasebe had cleared Naldo's attempt off the line.

Wolfsburg appeared to be heading for victory when Dzeko notched his second goal, in the 85th, after collecting a pass from Karim Ziani, with Mertesacker allowing the Bosnia striker to get clear.

Mertesacker made up for his mistake by knocking in the late equalizer.

In Mainz, Aristide Bance hit the Hamburg post in the third minute, but the visiting team replied immediately when Tunay Torun picked up a pass from Elijero Elia to slot home.

Elia had to leave the game in the 15th minute with an ankle injury suffered in a tackle from Nikolce Noveski, adding to Hamburg's long injury list.

Tim Hoogland grabbed the equalizer five minutes from time to protect Mainz's unbeaten record at home.

Hoffenheim lost at home for the second time this season and finished the match with 10 men after a red card for striker Maicosuel 10 minutes from the end. The Brazilian had only come on as a substitute in the 74th minute and was sent off for trying to snatch the ball from the hands of Dortmund's goalkeeper Roman Weidenfeller.

Dortmund took an early lead when Jakub Blaszcykowski scored in the third minute off a pass from Lucas Barrios and a loss of possession by Hoffenheim's captain Sejad Salihovic.

Demba Ba tied the game with a header from a corner by Carlos Eduardo early in the second half.

Dortmund secured the victory in the 79th when Nuri Sahin converted a disputed penalty, awarded when Josip Simunic was adjudged to have pulled down Neven Subotic.

Hertha Berlin, which finished last season in fourth place, appears on course for relegation after losing to Frankfurt. Hertha's coach Friedhelm Funkel knows Eintracht well after five years in charge of the Frankfurt team but Hertha never got into the match. No team has ever escaped relegation after collecting only five points in the first 14 games.

Patrich Ochs scored his first Bundesliga goal in three games to put Eintracht ahead, with Maik Franz and Alexander Meier completing the victory before Adrian Ramos pulled one back for Berlin.

Nuremberg fell to its fourth home defeat when Stefan Reisinger scored an early goal for Freiburg in a match between two promoted teams.