The sheep carcass was attached to the gate at Hanover's training ground alongside a message that rammed home the rivalry between the two clubs' supporters: "Sunday we're going to wipe the floor with you pieces of sewage."

Historically there has been a fierce rivalry between the two teams and even violence at their matches, which has only been exacerbated by both finding themselves involved in a relegation battle this season.

Braunschweig are rock bottom and four points from safety, while Hanover are only five points above the drop zone.

The sinister message left Hanover sporting director Dirk Hufner fuming.

"I can only say one thing -- it's lower than dirt," he said.

Three thousand police will be on duty in Braunschweig on the day of the match -- more even than for the North Rhine-Westphalia derby between Schalke 04 and Borussia Dortmund -- with 500 security personnel inside the ground.