Borussia Dortmund coach Jurgen Klopp has said he expects bitter rivals Schalke 04 to try and "spit in their soup" on Saturday with his team six points clear at the top of the league.
Dortmund beat second-placed Bayern Munich 1-0 at their Signal Iduna Park stadium on Wednesday and victory leaves them clear at the top with four games left as they look to register their 25th game without defeat.
With four consecutive wins over Bayern, Dortmund are only the second team in the history of the Bundesliga to have recorded a quartet of victories over Munich after Werder Bremen who achieved the feat between 1991 and 1993.
Third-placed Schalke host Dortmund in Gelsenkirchen and with no love lost between the neighbours, Klopp expects a hard match with their Ruhr Valley rivals which could help Bayern's chances of usurping the leaders.
"In terms of the table, we are in the lead, but on Saturday we expect another intense game," said Klopp, with the top three in the Bundesliga sure of a Champions League berth.
"They want to make sure of their Champions League place for next season and they will certainly want to spit in our soup."
After the Schalke match, Dortmund face fourth-placed Moenchengladbach, bottom side Kaiserslautern and Freiburg before the league finishes on May 5.
Bayern host Mainz on Saturday, then face Bremen, Stuttgart and Cologne in their last four league games, but Klopp says anything can still happen despite his team's considerable lead.
"We are just thinking about the next game, we have had three days to enjoy the victory (over Bayern), but after that we have another tough match ahead of us.
"We aren't there yet and, unfortunately, a lot can still happen."
Bayern, who host Real Madrid in the Champions League semi-final on Tuesday, face an uphill task to win this season's league title after a second-half goal at Dortmund saw them suffer their seventh league defeat of the season.
"You don't congratulate a rival until they're mathematically confirmed as champions, but I fear we can no longer prevent Borussia Dortmund winning the title," admitted Bayern chairman Karl-Heinz Rummenigge.
Bayern have little time to lick their wounds before Mainz and then Real arrive at Munich's Allianz Arena.
"We'll probably need two days to get over this, but after that, we'll go for it again in style," said coach Jupp Heynckes.
Goalkeeper Manuel Neuer has called for renewed efforts to keep dreams of a treble alive with Munich to host the Champions League final on May 19.
"We mustn't lose the plot now, so our heads have to stay up," said the Germany goalkeeper with his team to face Dortmund again on May 12 in the German Cup final.
At the other end of the table, the relegation battle claimed another victim on Thursday as Cologne replaced coach Stale Solbakken with ex-trainer Frank Schaefer.
Cologne were hammered 4-0 at Mainz on Tuesday and Schaefer has just four games left to steer his team from relegation as the side which finishes 16th in the league faces a play-off against the third best team in the second division.
Bottom club Kaiserslautern, who also dismissed coach Marco Kurz last month, will be relegated if they lose at Nuremberg on Saturday while Hertha Berlin, second from bottom, are at Bayer Leverkusen.
In the only weekend match played on Friday, VfB Stuttgart defeated Werder Bremen, 4-1.
Schalke 04 v Borussia Dortmund, Hamburg v Hanover 96, Kaiserslautern v Nuremberg, VfL Wolfsburg v Augsburg, Bayer Leverkusen v Hertha Berlin, Bayern Munich v Mainz 05
Borussia M'gladbach v Cologne, Freiburg v Hoffenheim