Michael Ballack struck early to give Bayern Munich a 1-0 win at home to Werder Bremen yesterday and keep the Bavarians top of the Bundesliga on goal difference.
Bayern's joy at beating last season's double winners and one of their two chief rivals for the title was tempered by an injury to Roy Makaay, however.
The Dutch striker suffered a thigh muscle strain that will keep him out of Bayern's Champions League clash with Arsenal on Wednesday, when the Germans will be defending a 3-1 lead.
Bayern moved ahead against Werder in the seventh minute when Ballack beat four Werder defenders in the air to power in a header from a Torsten Frings corner in the seventh minute.
Felix Magath's side maintained their lead with little difficulty against a curiously subdued Werder, who are now seven points off the title pace.
Bayern needed the win to stay ahead of Schalke 04, who kept up the pressure with a 2-0 win away to VfL Bochum.
With 24 games played, Bayern and Schalke have 50 points, followed by Werder on 43.
VfB Stuttgart moved up to fourth on 42 points with a 2-1 win at home to Arminia Bielefeld.
Bayer Leverkusen's faint hopes of getting back into the title race slipped further away when they were beaten 1-0 away by Hamburg SV, a result that leaves them in seventh place, now 11 points behind the leaders.
Bayern expect Makaay to be out for two weeks, meaning he will also miss next weekend's key Bundesliga match away to Schalke 04.
"It's completely bad news for us," said Bayern coach Felix Magath. "It's a big handicap in a crucial week."
Bayern stayed neck and neck with Schalke thanks to Ballack's early goal and a solid defensive performance.
There was none of the panache of their midweek 7-0 win over SC Freiburg, although the introduction of Paolo Guerrero early in the second half gave their attack a more dangerous look.
Guerrero almost added a second in the 61st minute when he showed brilliant control to bring a ball down in the area and lashed in a shot that Andreas Reinke did well to keep out.
Werder Bremen striker Nelson Valdez managed to round Oliver Kahn in the 73rd minute but he was unable to get in a clear shot from a wide angle.
Kahn had nothing else to do before holding a sweetly struck shot from Daniel Jensen in the final minute.