Jurgen Klopp has claimed the hostile atmosphere at the Wanda Metropolitano affected his Liverpool team -- and the referee -- in a 1-0 defeat to Atletico Madrid in their Champions League last-16 first leg on Tuesday.
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"It was like they could constantly go to the petrol station and we had to drive on one tank," the German manager said. "I don't know if [Atletico manager] Diego [Simeone] saw a lot of the game, because he was constantly animating the crowd.
"We speak about Anfield and the power a stadium can have, and tonight we saw it. They got a result, the stadium wasn't here to see sensational football, they got the result and so they are happy."
The crowd in Madrid also affected the official's handling of the match, according to Klopp.
"It was difficult for the referee to deal with the atmosphere tonight," he added. "There were a lot of situations, I think after 30 minutes three Atletico players were on the ground, they weren't even injured. The ref needs to feel the game a little bit more."
However, Klopp warned that Simeone's side can expect a similar reception at Anfield for the second leg in three weeks time.
"It's only 1-0, we're not 5-0 down," Klopp said. "We don't think it will be easy at our ground. For all Atletico fans who can get a ticket for the game, welcome to Anfield."
Simeone was delighted with a performance that saw his side limit what he called "the best team in the world" to not a single shot on target, despite having 72% possession.
"El Cholo" also pointed to the role of the fans, who had lined the streets with flares to welcome the team on arrival before kick off.
"In the eight years I've been here it hasn't often been at that level," Simeone said. "We started winning the game when the bus came around the roundabout outside and we saw so many people. It's not my best night, because we haven't won a trophy. But it's emotional. There are nights you don't forget, the best team in the world came here and we won the game."
Saul Niguez scored the only goal of the game just four minutes in, pouncing after Liverpool failed to deal with a corner.
"This is the result of hard work, of never stopping believing, of keeping going, even though no-one believes in us and everyone wants to bring us down," he said. "The atmosphere reminded me of the old nights at [the former Atleti stadium] Calderon."
Liverpool left-back Andy Robertson said Atleti's style of play and the early goal threw them off-kilter.
"We gave them the best possible start and that gets the fans behind them," Robertson told reporters. "Then they start falling over and getting under the skin a bit.
"We put in a decent performance and we know we can be better. We've got a second leg to put it right. They celebrated as if they had won the tie after the game. We have some weeks, then they come to Anfield. We know our fans will be there."
Klopp admitted that he had substituted star forward Sadio Mane at halftime because of fears he might receive a second yellow card and be sent off.
"It's part of football," he said. "I don't like it. The plan today was to get Sadio out of the game with a yellow card, I was afraid his opponent would go down if Sadio even took a deep breath. That's why I took him off."
The Liverpool coach also confirmed that captain Jordan Henderson was withdrawn with 10 minutes remaining as a precaution due to a hamstring problem.