The Reds had dominated the opening 72 minutes in west London, with Sebastián Coates’ spectacular overhead kick putting the visitors in front before Dirk Kuyt appeared to secure three points with a close-range finish.
But QPR came storming back as Liverpool suffered a meltdown, with veteran defender Shaun Derry and ex-Reds striker Djibril Cissé both scoring to level the game, before Jamie Mackie scored a 91st minute winner.
“I think they did [concentrate for the full 90 minutes], yes,” said Dalglish. “It’s not a lack of concentration. You’ve got to give QPR a bit of credit as well.
“We were so constructive in so many parts of our game tonight, but from a set play, a cross and then right at the death they’ve scored.
“We never got what we deserved, but it’s a tough life I suppose.”
Liverpool approached the trip to Loftus Road in good form, fresh from a 2-1 victory over Stoke City in the FA Cup quarter-final and a 3-0 win in the 217th Merseyside derby.
Dalglish admitted he did not see Liverpool’s collapse coming at 2-0, and the 60-year-old was unable to come up with an explanation for the shock loss which leaves his side 12 points adrift of fourth-placed Tottenham Hotspur.
“I don’t think anybody saw it coming,” he continued. “I’m sure there was a fair bit of feeling before the game about how we’d approach it and how the players would react to qualifying for a semi-final.
“But I think the way they started the game was fantastic with the passing and the movement. The only thing that was missing was a bit of luck in front of goal. We came in at half-time at 0-0, but it could have been three or four easily.
“We started the second half and got the goal – a great goal for Seb. Then Dirk touched one in and to be fair you couldn’t even see QPR getting a goal.
“But maybe the luck they never got at Bolton 10 days ago, they got tonight in the last 20 minutes.
“There is not much more we can say. We need to find answers and make sure we’re going to learn from it.”
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