(CNN) -- Bayer Leverkusen retained top spot in the German Bundesliga after coming away from second-placed Hamburg with a 0-0 draw on Saturday night.
Bayer Leverkusen's Daniel Schwaab, left, battles with Tunay Torun of Hamburg during Saturday's stalemate.
With both clubs still unbeaten on 21 points from nine matches, Bayer lead by the narrowest possible goal differential.
Home goalkeeper Frank Rost denied both Sami Hyypia and Stefan Kiessling in the final five minutes in a match of few clear-cut chances.
Hamburg coach Bruno Labbadia was without his two first-choice strikers Paolo Guerrero and Mladen Petric, and saw 19-year-old league debutant Tolgay Arslan come off injured soon after halftime.
Schalke closed the gap on the leaders to two points with a 2-1 victory at Stuttgart, while Werder Bremen kept fourth place with a 2-0 win at home to Hoffenheim.
Ivan Rakitic opened the scoring for Schalke at Stuttgart in the 24th minute, pouncing when Rafinha's high cross from the right was not cleared by Stefano Celozzi.
Stuttgart leveled 17 minutes from time as Julian Schieber broke free down the right to set up Cacau for his first Bundesliga goal of the season.
But striker Kevin Kuranyi struck the winner three minutes from Rafinha's throughball to leave his former club in 13th place with just one win in the last seven league games.
Hoffenheim fell to sixth place after a second successive defeat, paying the price for missing a first-half penalty with the scores deadlocked against Werder.
Bremen goalkeeper Tim Wiese went from villain to hero as he saved Carlos Eduardo's 14th-minute spot-kick after bringing down Brazilian midfielder Maicosuel, but needed Torsten Frings to keep out Eduardo's follow-up on the line.
Striker Claudio Pizarro put the home side ahead just four minutes later, as Eduardo on the Hoffenheim line could only deflect his header from a corner into the roof of the net.
Werder doubled the lead in the 22nd minute from another set-piece as Per Mertesacker poked home from close range following Mesut Ozil's free-kick.
Bayern Munich moved into fifth after returning to winning ways with a 2-1 victory at Freiburg, despite being without the services of Franck Ribery, Arjen Robben and Ivica Olic but boosted by the return of captain Mark van Bommel.
Young midfielder Thomas Muller put the visitors ahead three minutes before halftime after a shot by striker Luca Toni, making his first start of the season, was blocked by goalkeeper Simon Pouplin.
An own-goal from Cha Du-Ri doubled the lead in the 68th minute, as the South Korea international's backpass caught out Pouplin and rolled into the net.
Stefan Reisinger scored a consolation with the last kick of the game for 10th-placed Freiburg.
In Saturday's other matches, Cologne beat Mainz 1-0 to move away from the relegation zone, as did Nuremberg with a 3-0 home victory against bottom club Hertha Berlin.
Eintracht Frankfurt beat Hannover 2-1 to move onto 13 points alongside champions Wolfsburg, who host second-bottom Borussia Moenchengladbach on Sunday when Borussia Dortmund are at home to Bochum.