Schalke will have revenge on their minds as they make the trip to Borussia Dortmund on Friday for one of the biggest games in German football.
Not only were Schalke beaten at home by Dortmund earlier this season, but their hopes of winning the league title in 2009 were effectively ended by their local rivals when they were within touching distance of the silverware
Now, though, the boot is on the other foot with Dortmund marching towards the title this season and Schalke will be keen to put the brakes on their seemingly relentless push for glory.
Twenty-five points separate the two sides in the league table, but that does not mean it will be easy, claims Dortmund coach Jurgen Klopp.
"I would not say that we are outsiders, but we are not the overwhelming favourites either, which you may think given a look at the gap in the league table," he said.
"Schalke have extraordinarily high quality. It is easier to cause a positive surprise from a negative expectation."
Second-placed Bayer Leverkusen will be watching proceedings at the Westfalenstadion carefully since defeat for the league leaders would enable them to reduce the deficit at the top to eight points with a win at Nurnberg on Saturday.
Bayern Munich will also be hoping for a helping hand from the Royal Blues as they look to eat into a 14-point deficit by winning in Cologne.
Fourth-placed Mainz are also 14 points behind Dortmund and buoyed by their own derby win over Kaiserslautern last weekend.
They host crisis club Werder Bremen, who slipped onto the brink of the bottom three after losing to Bayern last weekend.
Borussia Monchengladbach and Stuttgart can also be defined as crisis clubs and their meeting at the Borussia Park Stadion on Friday evening could be decisive in their respective battles against relegation since the two clubs are locked together on 16 points at the bottom of the table.
Elsewhere, Hoffenheim host Kaiserslautern, while Hannover and Wolfsburg meet in a northern Germany derby on Saturday.
Sunday's games see a Hamburg city derby between HSV and St Pauli, before Freiburg end the weekend with their home fixture against Eintracht Frankfurt.