Borussia Dortmund face local rivals Schalke on Saturday hoping to cap what could prove to be the decisive week in the Bundesliga title race with a three-point haul.
Dortmund opened up a six-point gap at the summit with a 1-0 home win over nearest challengers Bayern Munich on Wednesday night, and another victory over third-placed Schalke - the toughest looking of Borussia's four remaining fixtures - would leave the defending champions on the cusp of the title.
Dortmund captain Sebastian Kehl admits it was a huge result to defeat Bayern, but insisted there is still work to do.
He said on his club's website: "That was a very, very important step for us, of course, but we must not forget that we have another major game on Saturday, the Ruhr derby against Schalke. One thing is clear. We have not won anything yet this season."
If Dortmund, who have not lost in 24 Bundesliga matches, slip up in Gelsenkirchen then Bayern will hope to halve the deficit between the two clubs with a home victory over mid-table Mainz.
Bayern admit the title is now well within Dortmund's grip, though, with winger Arjen Robben saying following last night's defeat: "Dortmund have taken a huge step and we can almost say that they are champions."
At the other end of the table, Kaiserslautern are just one more defeat away from losing their top-flight status and need to beat Nurnberg.
The Red Devils have not won since October 22 - a run of 20 games - and the appointment of Krassimir Balakov has failed to turn things around. In fact, he has lost his three games in charge and not even a point on Saturday will be good enough to at least postpone their impending relegation to the second division after two seasons in the Bundesliga.
"We have got to be realistic," he told Sky television. "We know that we are close to the second division. Only theoretically do we have any chance of staying up and we will try to take this to the very last game of the season."
Second-bottom Hertha Berlin are also in desperate need of points as they travel to Bayer Leverkusen, while 16th-placed Cologne need to win their local derby at Borussia Monchengladbach to have any chance of getting out of the bottom three this weekend.
Augsburg, in 15th, travel to Wolfsburg while Hamburg are the other club still in danger and they host Hannover on Saturday.
Above the bottom five, Freiburg, Nurnberg and Mainz all edged away from trouble with wins in midweek and their Bundesliga status could be sealed with victories this weekend. Freiburg host Hoffenheim on Sunday.
Elsewhere, the battle for a place in the Europa League intensifies with fifth-placed Stuttgart hosting eighth-placed Werder Bremen on Friday night. The two sides are separated by just four points with Leverkusen and Hannover sandwiched in between the pair.
Wolfsburg and Hoffenheim are also lurking just behind Bremen with this battle likely to go down to the wire.