Jurgan Klopp was unhappy with both the refereeing and PSG's spoiling tactics as Liverpool suffered a damaging 2-1 defeat in Paris that could spell the end of their Champions League hopes.
The Reds boss was unhappy with the hosts' play-acting and highlighted Neymar's role as the Ligue 1 club consigned Liverpool to a third away defeat in Group C.
Six Liverpool players were booked and only two for PSG, although there was an argument midfielder Marco Verratti could have been sent off for an over-the-top challenge on Joe Gomez, and Klopp said it made his team look like aggressors.
"The number of interruptions in that game was just not cool," said the German. "Two times in a row we won the Fair Play award in England and tonight we look like butchers after the yellow cards we had.
"It was clever of PSG, especially Neymar, but a lot of other players went down like it was really something serious and we were not that calm any more.
"We were aggressive, and unfortunately negative aggression doesn't help in football, we got rather frustrated and angry.
"But we have to deal with it, that's our job. If the ref lets that happen then we have to deal with it."
Asked if the referee could have handled it better Klopp added: "There are a lot of things you can do. You can give yellow cards for everything.
"If you go down, you act like you die and then the next moment you get up, yellow card. It's possible. It's unsportsmanlike behaviour.
"In the end, it's hectic and everyone is going down. I don't expect help from a ref, I just expect him to calm all these things down.
"The crowd was up, it's really difficult and we were not calm enough. Even Joe Gomez got a yellow card. He's the nicest boy on this planet and he was close to getting a red."
The result leaves Liverpool having to beat Napoli at Anfield either 1-0 or by two clear goals to progress to the knockout stage, but before that they face Everton in Sunday's Merseyside derby..
"We need Anfield again and we need to create an atmosphere which is pretty special. We know that," Klopp said.
"But Napoli is a really strong side. If we go through we deserve it, and if not then we don't.
"We are not afraid of that, and I believe you get what you deserve. That's it. We have to try everything."
