Borussia Monchengladbach are just one win away from securing a place in the Champions League next season after beating local rivals Cologne 3-0 at the Borussia Park Stadion on Sunday.
Juan Arango gave the Foals a 1-0 advantage at half-time and two goals in as many minutes from Tony Jantschke and Marco Reus sealed the win for Lucien Favre's side, taking them seven points clear of fifth-placed Stuttgart and to within a point of Schalke in third.
Cologne, meanwhile, remain in serious relegation danger after failing to show any signs of life in Frank Schafer's first game as coach.
They are now four points adrift of safety and just a point ahead of Hertha Berlin, with both sides now likely to decide between them who goes down automatically and who gets a second chance in a play-off.
Gladbach had as much reason as Cologne to want to win this derby with Stuttgart starting to close in on them and threaten their chances of qualifying for the Champions League, and they started brightly.
Mike Hanke's curling volley seemed to be arcing towards the far corner, but Michael Rensing made a good save at full stretch to push it wide in the third minute.
The home side took the lead in the 19th minute with Arango curling a direct free-kick over the Cologne wall and into the top right-hand corner, beyond the reach of Rensing's desperate dive.
Reus had a volley tipped over by an increasingly busy Rensing in the 22nd minute and the former Bayern Munich goalkeeper made another crucial stop to deny Mike Hanke in the 40th minute after he was put clean through by Reus.
It was not the first time Rensing had kept Cologne in a game this season, but there was little he could do to prevent a collapse in the space of just two minutes early in the second half.
First, Jantschke headed Reus' free-kick past him and then Reus got his name on the scoresheet himself.
The Germany international took the ball through almost unchallenged and, although Rensing got his foot to the ball, he was unable to keep it out as the shot grazed the inside of the post on its way in.
Rensing then prevented Cologne from further damage by denying Arango's low shot in the 69th minute before tipping Roul Brouwers' header over.
