The Reds resume their Champions League campaign on Tuesday night as they travel to Wanda Metropolitano to face Diego Simeone's side.
The reigning European champions will be looking for a positive result to take back to Anfield for the second-leg next month.
A 21-man Reds travelling squad touched down in Spain on Monday afternoon before making the trip to the stadium and finalising preparations ahead of the tie.
Klopp was joined by Reds right-back Alexander-Arnold in facing the media as the duo looked ahead to a tantalising 90 minutes in Madrid.
'We Have To Work Our Socks Off'
The Reds boss urged his side to be at their best, emphasising Atletico's ability to frustrate sides and counter them - ideal for two-legged knockout matches in Europe.
"If there is a team where you have to, you have to, be at your absolute best in all departments it is Atletico. There are no presents tomorrow, absolutely no presents," Klopp said.
"If you work as hard as possible then you have a chance, but if we don’t do that then we don’t even have a chance. That’s exactly like it is.
"There is a reason why Atletico were that often in European finals as well. Now not for, I don’t know exactly, two or three years or so, but before that and it just shows how long they’ve worked together.
"It is normal you have to change it a little bit; they had to change, they did that, brought in big potential, some experience and it is completely normal. We cannot think about that, I see a team playing and for me, it looks like a real proper machine.
"It is like whatever happens then they are there, in the moment when you are not 100 per cent focused or concentrated, they close you down with two players, three players, however many they need and then counter-attack.
"If you are not focused and concentrated in your own offensive stuff, then you will not even have a shot on target because they close the centre so good, they defend in a specific way.
"It is all clear but on the other hand side, I don’t think a lot of teams – if they didn’t play against us [already] – have played against a team like us. We should not forget that.
"We combine a few things, we are not bad organised as well, we play football, we respect different aspects of the game I would say. [Our] readiness to fight is exceptional.
"We don’t feel like the winner of last year’s Champions League tournament, we feel like one of the contenders for this year’s – and we want to show that.
"We want to be there in Istanbul if possible and for that we know, historically in our own history and in general, you have to what work your socks off and that’s exactly what we have to be ready [to do] tomorrow. Hopefully, we can show that."
What Trent Had To Say
Alexander-Arnold insists Liverpool aren't looking too far ahead, with their focus solely on the next task at hand.
The Reds clinched number six at the same stadium back in June last year, but Alexander-Arnold isn't keen to dwell on the past.
"Obviously it holds good memories for us where a lot of our dreams came true, but for us we can’t focus too much on the past," he said.
"We’ve got a job to do tomorrow. Our aim is to hopefully win these type of trophies and keep going in each type of competition as much as possible.
"Our next step is to try and get a result tomorrow and we know it will be difficult. That's where our focus is at and we're not focused on what happened in June, we’re focused on what's going to happen tomorrow."
Liverpool are on course for the greatest-ever Premier League triumph, but the squad remain motivated to ensure it's a successful season on all fronts.
"We want to achieve as much as possible. We want to make the most of it while we can, so for us it’s about trying to do the things that we did last June," he added.
"In terms of changing the focus, nothing has really changed for us because we go into every game with the same mentality that we respect the opponent as much as we can.
"We understand that we're a really good side and that if our mentality is right and commitment is right in the game then we have a chance. Whether that be in any competition we take part in, we’re confident going into the game."