Liverpool and Manchester United fans have warned their fans against obscene and vulgar chanting in Monday's Premier League fixture at Anfield.
Tensions often run high on the pitch and in the stands when the great rivals meet, although that has manifested itself in the form of tasteless songs from both sides.
And a joint-statement released ahead of the game by both United and Liverpool served as a caution to attendees that they risk arrest if such chants are brought up again.
It read: "Both clubs, their supporters and football fans around the world are looking forward to this historic and passionate match between two of the sport's biggest and oldest rivals.
"There is great rivalry between our fans and we ask all supporters to be respectful and help eradicate all forms of offensive and discriminatory behaviour from the game.
"If any supporters are found to be engaged in any form of offensive or discriminatory behaviour by stewards or via CCTV then they will be immediately removed from the stadium, risk arrest, prosecution and be reported in accordance with the club's ground regulations.
"This is an unrivalled fixture in the Premier League calendar and we thank all fans for their continued support in this important area of the game."
Anti-racism campaign Kick it Out, added: "Both Liverpool and Manchester United should be commended for this proactive approach ahead of this important fixture."