Jurgen Klopp insists he is calm in comparison to fiery Atletico Madrid boss Diego Simeone

There were smiles and lavish compliments; there was respect and admiration but, most candidly of all, there was a stark warning.

Jurgen Klopp was full of life in the Wanda Metropolitano, as you might expect given the surroundings. He was perched in the same chair he sat in 262 days ago, when he gained entry into the exclusive club for Champions League winners, but this time his enthusiasm was for Diego Simeone.

Liverpool’s manager rattled platitudes for Simeone, as if they were heading out of fashion, at one point referring to Atletico Madrid as ‘a result machine’ and himself as ‘a kindergarten cop’ in comparison to the Argentine, who will once again fizz like a human Catherine wheel.

Jurgen Klopp was full of life in the Wanda Metropolitano during his press conference

‘He has been eight years and still has that emotion?’ Klopp remarked, with a pause for effect. ‘Wow! I’m only on level four… Diego is on level 12!’

Underneath the veneer, though, Klopp was deadly serious about what is in store tonight at a stadium that Simeone says will be ‘ready to explode’ with desire. Atletico poses a serious threat to Liverpool’s ambitions, so much so that the German feels his team are now back on a tightrope.

One of the remarkable statistics during Klopp’s reign is that Liverpool have not lost a European knockout game – their record is a perfect 10 from 10 in the Europa League and Champions League – but if the intensity drops for a second in these two games, that number will be consigned to dust.

‘If there is a team where you have to be at your absolute best at all times, it’s Atletico,’ said Klopp, who is expected to name his strongest team. ‘They give no presents. Absolutely no presents. If you work as hard as possible, then you have a chance. If you don’t, then you don’t even have a chance.

Diego Simeone is known for being an animated character on the touchline during matches

Diego Simeone is known for being an animated character on the touchline during matches

‘That’s why Atletico were often in European finals. It shows how long they were together, and now they had to change, they did that, brought in big potential, some experience. I see a team playing and, for me, it looks like a proper machine. Whatever happens, they are there.

‘The moment you are not 100 per cent concentrated, they close you down with two or three players and then counter-attack. If you are not focused and concentrated in your own offensive play, you will not even have a shot on target because they close the centre so good.’

The message was repeated by Trent Alexander-Arnold, who woke on Monday to find that Cafu – the Brazil World Cup winning captain who set the gold standard for the modern right-back – had tipped to win the Ballon d’Or in the future.

‘Just because we have been to two finals, it doesn’t mean we are going to get there this year,’ said the England international. ‘This is knockout football and things can happen. But in things that we have learned, we understand what it takes.

Trent Alexander-Arnold was speaking ahead of the Champions Last-16 tie in Madrid

Trent Alexander-Arnold was speaking ahead of the Champions Last-16 tie in Madrid

‘The experience we have had over the last two years means we know how to deal with certain situations. If we were not at 100 per cent, we will get punished. We have to be at 100 per cent – otherwise we will be out.’

Respect, however, should not be confused with trepidation. Liverpool have been to Kiev and Madrid to contest the last two finals for a reason and a return to Istanbul – and the potential to retain their title – is a huge motivation for a squad that is careering towards the domestic crown.

‘I don’t think they played against a team like us – and we should not forget that,’ said Klopp. ‘We combine a few things, we are not badly organised, we play football, we have respect different aspects of the game, our readiness to fight is exceptional.

‘We don’t feel like the winners of last year’s tournament, we feel like contenders for his year’s, and we want to show that. We want to be there in Istanbul if possible, and for that we know we have to work our socks off.’

Mohamed Salah (left) and Dejan Lovren (right) on the Wanda Metropolitano pitch on Monday

Mohamed Salah (left) and Dejan Lovren (right) on the Wanda Metropolitano pitch on Monday

It promises to be an intriguing collision between sides that last faced each other in the Europa League semi-final in April 2010. Liverpool, back then, were a mess off the field, torn apart by internal fighting and a squad that had been broken up to pay off the debts.

This group is going from strength to strength and their march has taken Simeone by surprise.

‘We have always spoken about great teams throughout time,’ said Simeone. ‘I have no doubt this Liverpool is going to go down in history as a great team because it is different to teams that we have admired (in the past).

‘He has been improving even after Coutinho left. It could look as if the team was breaking up, but on the contrary the team has become even stronger. That says a lot about the footballers who are still with Liverpool.’

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