Robin van Persie and Nemanja Vidic both struck inside the opening 55 minutes before the Merseyside outfit burst into life, with substitute Daniel Sturridge halving the deficit.
Despite Liverpool enjoying a dominant spell to end the match, Brendan Rodgers’ side were unable to rescue a point, and Downing felt the visitors were made to pay for a lacklustre first half.
“In the end we’re disappointed that we didn’t take anything out of the game. We should have got a draw,” Downing told the Liverpool Echo.
“We probably let them control it in the first half. We sat back too much and just let them have the ball too much.
“We showed United too much respect. The manager stressed at half-time that we needed to push on and put them under pressure more when they had the ball.
“He said if we could get at them they would tire and we would get chances. We did that and you saw that in the second half we played further up the pitch.
“I thought in the second half our performance was really good. Certainly for the last 20 minutes we had them pegged right back.
“You could sense that their fans were getting edgy and Alex Ferguson was shouting a lot of instructions. We had them rattled a bit and created plenty of chances.”
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