They are arguably the two most high-profile managers active in the world of football today.
In many ways the two coaches could not be much more different to each other.
From their tactical styles and man-management methods to their dealings with the media and on-camera demeanor, it’s fair to say their styles are chalk and cheese.
You would expect this to lead to the kind of overly conspicuous clashes we have seen between Mourinho and Arsene Wenger or Klopp and Frank Lampard in recent times.
Yet the psychological warfare between Mourinho and Klopp tends to take form in a far more subtle, understated manner – which makes it all the more interesting to analyse.
Take Mourinho’s recent reaction to Klopp winning the FIFA coach of the year.
The German was the surprise victor of the gong over Bayern Munich’s Hansi Flick, who had won a superb five trophies last season including the Champions League and Bundesliga.
When asked for his reaction Mourinho had clearly carefully pre-planned his response, and rather than congratulating Klopp obviously wanted to take him down a peg or two.
“I think the only chance for poor Flick to win is that Bayern finds two or three more new competitions to win it,” he joked, cleverly pouring cold water on Klopp’s achievements without explicitly saying anything.
Klopp now had the option to fire back at Mourinho, but rather than doing so he instead avoided an unnecessary war of words by agreeing – something which will no doubt have disappointed the Portuguese, who is constantly looking for ways to rattle his opponents.
Indeed, it would be no surprise if secretly Mourinho resents the fact that Klopp never seems to rise to his bait.
Most recently, in Liverpool’s late 2-1 victory over Spurs in December, Mourinho slammed Klopp’s animated style on the touchline, telling reporters: “If I behaved the same, I’ve no chance to stay there.
“The referees let him behave the way he does. It’s not my problem. I feel sad for it because I cannot do it, but it’s just the way it is.”
Again, Klopp kept a cool head with his response, saying: “Come on, that’s animated? He wasn’t happy because he told me the better team lost – and I thought he was joking. But he wasn’t. So that’s it.”
Klopp’s calm reaction to Mourinho’s suggestion that the best team lost will have again rankled the Spurs boss, who would have been hoping for a more dramatic outburst.
Yet despite the obvious underlying needle between the duo whenever they face off, there is still an undercurrent of respect present.
Mourinho admitted before the upcoming match the two were not friends, but added: “He’s a colleague that I respect, that I don’t have any problem with. He’s the same with me, no problems at all.”
Klopp, on the other hand, also clearly enjoys testing himself against the likes of Mourinho, and seemed genuinely disappointed when he was sacked as Manchester United boss.
He said at the time: “He’s a very competitive guy. Very ambitious. Really competitive. He has all my respect. He is an outstanding manager.”
So what should we expect from Thursday’s latest instalment and going forward into the future?
The history between the two suggests they are never likely to come to physical blows on the touchline a la Mourinho and Wenger.
Instead they tend to play their moves like in a chess match, carefully weighing up whether their words can gain them any marginal advantage over the other.
Ultimately the results are the most important thing, and the fact of the matter is that Klopp has won his last three encounters in a row against Mourinho.
Whether that becomes four on Thursday remains to be seen, but whatever the result between the two sides, Mourinho v Klopp is likely to dominate the headlines once again.
It is a captivating rivalry which only looks likely to continue into the near future.