Jose Mourinho and Jurgen Klopp are not only two of the world's top managers, but big characters also.
And the fact that both bosses will meet at Anfield tonight is almost a headline of it's own - regardless of the fact that the biggest rivalry in English football is set to take place.
Liverpool versus Manchester United will always draw in a massive audience from around the globe, but the clubs' respective managerial heavyweights are also gaining some attention this time around.
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However, it's not the first time Klopp faces Mourinho as Reds boss, after coming from behind to beat Chelsea 3-1 at Stamford Bridge last October for his first win in charge, as the Portuguese headed for the sack.
Mourinho has already made some subtle digs in the German's direction, to which Klopp has refused to get involved in a war of words. But in his latest attempt to seemingly irritate his opposite number, the former Chelsea boss has admitted his dislike for Klopp's behaviour in the dugout.
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The German is animated to say the least and even, at one stage last season, saw his glasses broken after a manic celebration with his Liverpool players following a dramatic late 5-4 win over Norwich.
And the 49-year-old has been seen involved in similar celebrations again this campaign; during the Reds' dramatic 4-3 win over Arsenal on the opening day of the season.
Mourinho, though, hopes his rival will be able to stay more composed on the touchline tonight, when English football's two biggest rivals come head-to-head on Merseyside.
Mourinho rejects Klopp antics
Heading for the exit, following his pre-match press conference, Mourinho was asked for his thoughts on Klopp's touchline antics.
Putting it simply, as per the Daily Mail, the Portuguese responded: "I'm on the touchline to try to coach.
"I'm not on the touchline to …" Mourinho said, before trailing off into a more Klopp-like expressive nature - flapping his hands in the air.
But not that this will be news to Klopp, who is already aware that Mourinho is not so fond of his touchline antics and the Portuguese has dismissed any suggestions that he was in anyway like the German during his early days in management.
"We don't press referees, we behave on the touchline, so that is a point we are very comfortable with." said Mourinho, after the pair's previous meeting a year ago.
Klopp did confess at the Emirates, on the opening day of the season, that his celebrations were premature - although, not over the top - considering Arsenal were to get themselves back into the game.
However, it would be highly surprising if the German was to tone down his infectious character for the sake of Mourinho in what he knows is a massive game for his Liverpool side.
And with Klopp having enjoyed a fine start to the campaign, he will no doubt be prowling the touchline with excitement rather than anxiety, when Mourinho's United side arrive in town on the back of one win in four league games.
Is Jurgen Klopp's touchline behaviour fair for other managers? Give your opinion in the comment box below.