Liverpool manager Jurgen Klopp has suggested that his team's Europa League meeting with Manchester United has a claim to the title of "the mother of all football matches".
The two teams have one of the longest-standing, and most keenly felt rivalries in world football, but have never met in European competition before.
It means that Thursday's round of 16 first-leg meeting at Anfield will be a first, and Klopp sees it as one of the biggest matches on show anywhere in the world.
That is despite the fact that they will be meeting in European football's secondary club competition rather than the Champions League.
"Games like this are the mother of all football games. That's what you want when you are young. These games are easy, because they are so big. You don't have to think about concentration because you are absolutely focused.
"It's big. I don't have to compare games. If you work in Dortmund, as I did, and you play against Schalke, it's not possible to talk about anything else.
"It's similar here with this fixture. It's a really big game. I hope it's not the biggest in my Liverpool career, but it's very important."
Liverpool's manager is used to facing his United counterpart Louis van Gaal, as they were regular opponents in the Bundesliga.
Klopp was in charge of Borussia Dortmund when he enjoyed a good run of victories over Van Gaal, then at Bayern Munich.
"I don't believe in enemies in football. I believe in real opponents. Absolutely no problem with Louis van Gaal but the last thing I want is for him to win.
"He is one of the most successful managers in the world. The first time my Dortmund side faced his Bayern Munich side, I think we lost. In fact, we probably lost.
"But we learned to take the Bayern style and to play pretty well. We had the longest run of winning games against Bayern Munich in the history of German football.
"I'm pleased he changed the situation at Manchester United when it was not going well, because at the end of a long career it was not good what was being written about him.
"A few people were writing as if he had no idea about football. He changed enough that things have improved.
"We want to make their problems bigger by winning the game, but we can win and we don't have to be sorry for Manchester United."
Liverpool have lost their last four matches against Manchester United, and a fifth defeat on Thursday would create an unwanted club record.
Midfielder Adam Lallana is keen to put an end to that run.
He said: "I've not won a game against Manchester United since I've been here so it's a great chance to put that right.
"We've still got a few local lads in the squad but you don't have to be local to realise the significance of the match.
"There's something special that rides on a game against Manchester United. We've spoken about our form in the last four games against them, and we want to end that run."