The pair were at fault for Manchester City’s goal in the League Cup final after Fernandinho managed to evade Moreno and squeeze a finish past Mignolet’s near post.
The mistake is shocking. You can’t score from there
Liverpool went on to lose 3-1 on penalties after Lucas Leiva, Philippe Coutinho and Adam Lallana missed their spot-kicks at Wembley on Sunday afternoon.
Former Liverpool defender Carragher was merciless in his evaluation of Moreno, urging Klopp to place his faith in his former team-mate, Jon Flanagan.
“The left-back has to come out of the team, this is not a one-off in terms of the goal,” Carragher told Sky Sports.
“Jon Flanagan has come back fit and has to go into the team in midweek, he has to change the left-back.
“Flanagan played left-back when they nearly won the league. He can’t be worse than him [Moreno].”
Mignolet signed a new five-and-a-half year deal at the 18-time English champions in Janaury despite an error-strewn season.
Former Liverpool centre-half Carragher believes the Reds need to sign a top goalkeeper to replace the Belgium international.
Carragher added: “The goalkeeper has made some outstanding saves today, but just because you make some outstanding saves doesn’t mean you should be allowed to concede a goal like that.
“The mistake is shocking. You can’t score from there. And that is not just today [Sunday].
“Going forward for Liverpool, those are two areas Jurgen Klopp has to change in the summer.
“The goalkeeper may have signed a five-year deal, and he has made some good saves, but things have to change.”
Liverpool host the Citizens in the Premier League on Wednesday night at Anfield in a repeat of Sunday’s final.
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