Brendan Rodgers’ side made a bright start to the match, but Shelvey was issued with a red card in the 39th minute after a challenge with Jonny Evans.
Gerrard put Liverpool ahead despite the numerical disadvantage, but Rafael’s superb strike and a late Robin van Persie penalty wrapped up three points for the visitors.
“We played really well today with 11 and even better with 10 so it’s disappointing,” said Gerrard.
“It’s not a red card. I’m not going to stand here and say a Manchester United player should be sent off but you look for consistency and if he [the referee] is adamant it was a red then Jonny Evans should have had a red as well. I knew at the time it wasn’t a red.
Liverpool enjoyed 52 per cent of the possession in a feisty north-west derby, with Rodgers’ side testing Anders Lindegaard on 14 occasions.
Gerrard was encouraged by the Reds performance, and the 32-year-old insisted the Merseyside outfit would be fully motivated to claim their first win of the season against Norwich City next weekend.
“If we keep playing like that and showing that determination it won’t be long [until we get a first league win of the season],” he added.
“We are not going to keep blaming luck and keep making excuses and we need it at Norwich. We will keep plugging away.”
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