Roma head coach Eusebio Di Francesco says there are "rotten apples" within all football club fanbases and insists the Italian side are "united against all forms of violence".
Liverpool held an extraordinary meeting with their Italian counterparts last Friday after Reds supporter Sean Cox was left in a critical condition after he was attacked by a group of Roma fans outside Anfield before last week's Champions League semi-final first leg.
Jurgen Klopp's team hold a 5-2 lead after former Roma player Mohammed Salah scored twice to give Liverpool a commanding lead but much of the pre-match conversation has surrounded safety concerns in the Italian capital.
"I am afraid there are rotten apples everywhere in all sets of fans. Obviously someone who does not belong as a true fan did something very wrong and my thoughts and prayers go with the family (of Sean Cox)," Di Francesco said at the pre-match press conference.
"What I can assure you is that here in Rome the base of Roma fans are very passionate. Unfortunately hooligans are everywhere and you are familiar with that phenomenon.
"Unfortunately it is a massive issue that is detrimental to the whole football world so my appeal to fans is to come to the stadium and enjoy a festival of sport."
Liverpool have issued guidance, along with a list of other safety and security recommendations to their travelling supporters, with fears of further trouble in Rome.
Ahead of the return fixture, Liverpool has called on supporters to avoid walking to the stadium "under any circumstances" as part of the ongoing collaboration between the two clubs and UEFA.
Di Francesco is adamant that the issue of fan safety is wide-ranging in the game and is optimistic the meeting will go without further trouble.
"The club and I stand shoulder to shoulder with Sean Cox and his family and we are united against all forms of violence.
"The vast, vast majority of Roma fans are true and well-meaning supporters. I hope it's an enjoyable occasion tomorrow."