England's champions-elect face a battle to retain their European crown after Liverpool suffered in Madrid with a 1-0 loss to Atletico.
But Jurgen Klopp insists his side are still in the tie ahead of the second leg in three weeks' time.
"Our people will be ready, welcome to Anfield, it's not over yet," he said.
An early goal from Saúl Ñíguez was the difference between the sides, Diego Simeone with the tactical masterclass which the Reds had no answer to.
Liverpool's much-vaunted attack failed to spark in the Spanish capital as Atletico looked in control and bossed the game to frustrate Jurgen Klopp, who was booked on a night where the Reds failed to land a shot on target.
It was a nightmare start for the Reds when they were a goal down after only four minutes, Ñíguez with a close-range finish.
Atletico boss Simeone had done his homework and the home side were able to frustrate the reigning European champions.
Klopp later said he substituted Sadio Mané at half-time, when he was on a yellow card, as the forward had been "targeted" by the Spanish side.
"The early goal was not what should happen, apart from that it was the tie we expected, the atmosphere," Klopp said.
"What we lacked was in the final third, they defended with all they had, we had moments and came though but didn't hit the ball clear. Nil-nil would have been okay. We take it, and we look forward to the second leg."