QPR manager Julien Stephan felt his side never got going in their 2-0 Championship home defeat to Sheffield United.
Stephan was also aggrieved Richard Kone's header was ruled out for offside, which would have made it 2-1 with 17 minutes to play.
He told BBC Radio London: "Tough result, tough performance. I'm disappointed with the performance, to concede the goals too quickly in the first half.
"We didn't start the game like we expected to in terms of aggression or intensity. It was better in the second half, but we didn't succeed in creating strong momentum.
"We scored one goal, I think. It should have been 2-1 at that moment and that would have changed completely the momentum for the end of the game.
"But I don't want to explain only this result with this decision. It had a strong impact, especially if I compare the goal Liverpool scored today and it was exactly the same.
"So there's a big difference in terms of decisions between the Premier League and the Championship. But this is the history of this game and we didn't show enough quality today to hope for a better result, especially in terms of intensity and mental strength."