Hamburg have never been relegated from the German top flight, and are the only club to have competed in the Bundesliga each season since its inception in 1963, but Bert van Marwijk's side currently sit in the drop zone having lost five in a row.
Beckenbauer, who won the 1982 Bundesliga title as a player with Hamburg, believes the current crop of players must do all they can to avoid relegation - something he felt was unthinkable.
"I cannot imagine HSV in the 2. Bundesliga," he told Sky90.
"That's why everything needs to be done. This can't be happening that they descend into the 2.Liga."
"In the head they need to be free, then they can play football. Maybe they understand it now."
Hamburg take on Hertha Berlin at the Imtech Arena on Saturday, before travelling to the league's bottom side Eintracht Braunschweig a week later.
