A win for the hosts would stretch the point gap between Roy Hodgson's side, who currently take of the final spot inside the drop zone, and themselves to seven points with seven fixtures left.
Home advantage has proved to be crucial
The Terriers have achieved monumental results at the John Smith's Stadium in their debut season as a top flight club, including a 2-1 feat over Manchester United, which have helped their fight for safety.
Victories against fellow strugglers AFC Bournemouth, Newcastle United and West Bromwich Albion have also been highly beneficial in front of support which has earned endless amounts of plaudits this term.
Wagner has issued a rallying call for the same set of fans ahead of the weekend's highly-anticipated clash, stating: "In front of our crowd in the John Smith's Stadium, if there was one game in the club's history where you have to stand up and support your football club then it's tomorrow."
He added: "You have to make our stadium special. This has to be a further step for all of us, on the grass and in the stands."
Backing from the stands must be "extraordinary"
Town's German head coach publicly explained the importance of victory against The Eagles, a victory which would mean the West Yorkshire club may be able to start to smell safety.
Speaking on what he needs from the fans on Saturday afternoon, Wagner stressed: "It has to be extraordinary, something we have maybe never seen before because this game is a very, very interesting and exciting one.
"We can make the gap bigger between Crystal Palace and us, this is our aim that we would like to do."