Jurgen Klopp believes Manchester City captain Vincent Kompany should have been sent off in Liverpool’s defeat at the Etihad.
Kompany escaped with only a booking for a heavy first-half challenge on Mohamed Salah.
City won 2-1 as Leroy Sane’s 72nd-minute winner cut Liverpool’s Premier League lead to four points.
“I really like Vincent Kompany but how on Earth is that not a red card?” asked Liverpool boss Klopp afterwards.
“He is last man and he goes in. If he hits Mo more he is out for the season.”
Kompany disagreed with Klopp’s assessment of his challenge which came about from an under-hit square ball from City team-mate John Stones while the game was still scoreless.
“I thought it was a great challenge, was it not? I got the ball, a little bit of the man but it wasn’t naughty,” the Belgium international said.
“I didn’t try to injure him. It was that or let him go through on goal.”
Klopp said that his team did not play at their best, but could consider themselves unlucky after Sadio Mane hit the post and Stones cleared off the line moments later in an early goalmouth scramble.
“Our expectations are high. We can play better. You have to take the game how it is. You can’t always dominate it,” he added.
“We were unlucky in our finishing moments. Unluckier than City I would say.”
The defeat was Liverpool’s first in the Premier League this season, ending hopes that they could repeat Arsenal’s 2004 feat of going a whole league season unbeaten.
But Klopp insisted that a four-point advantage over the defending champions with 17 games remaining was a strong position for his side to secure a first league title since 1990.
“If somebody had told me after both games against Man City we would be four points up, I would have paid money,” said Klopp.
“We want to finish the season as strongly as possible and we are still in a pretty good position.
“I have already said to the boys this is OK. We lost it but it will happen. Tonight it is not nice but it is not the biggest problem.”