Jurgen Klopp was left furious that referee Martin Atkinson failed to award Liverpool a penalty for an apparent handball against Shane Long as the Reds crashed out of the EFL Cup semi-finals to Southampton.
Long scored a late winner in Wednesday's second leg at Anfield to secure Southampton a 2-0 aggregate victory and a trip to Wembley to face either Manchester United or Hull City.
Liverpool manager Klopp conceded that this side should have done more with the chances they created, but felt that Atkinson was wrong not to award a spot-kick for what he felt was a handball by Long.
The German claimed it was not the first time his side had been denied an obvious decision by the officials this season and was unable to hide his frustration.
"The ref did not see the handball of Long and it does not help in a game like this," Klopp told BBC Sport.
"If we could hear a referee's whistle it would be nice. I do not know how many times that has happened this season.
"Against Manchester United we had a clear offside goal [scored against us by Zlatan Ibrahimovic], nobody says anything. Tonight [Wednesday] a penalty, nobody says anything."
On Southampton's win and Liverpool's finishing, he added: "They won both games, they deserved it.
"We did really well, we cannot create more chances than we did in the second half, we were dominant. It is difficult because you have to take risks but too many risks plays to their strengths.
"We had big chances and no luck. A lucky save [from Fraser Forster], a good save but a lucky save.
"We had seven good chances. You have to score, and we did not do so we lost. I am fine with the performance but not the result."