The Belgium international made two saves to deny Stoke players Peter Crouch and Marc Muniesa before Joe Allen scored the winning spot-kick to send Liverpool through to their 12th League Cup final.
Mignolet signed a new five-and-a-half year deal with the Merseyside outfit earlier this month despite his error-strewn performances throughout the 2015/16 campaign so far.
While Carragher wasn’t getting carried away with Mignolet’s heroics in the semi-final second-leg tie, the former Liverpool defender is optimistic the penalty shootout win will give the shot stopper a much-needed lift.
“He has made two saves. One of the keepers in every shootout is going to be the hero,” Carragher told Sky Sports.
“He has had plenty of criticism. You don’t become a great goalkeeper because of a penalty shootout.
“He has a lot more to do in his Liverpool career but that should give him a massive lift.”
Carragher continued: “The club has given him a lift in terms of giving him a five-year contract. A lot of supporters were scratching their heads when that come out.
“Hopefully, that will give him a massive lift. You want to see Mignolet doing well. You want Liverpool to have a top goalkeeper. He has been here so long and you still have questions marks against him.
“It should give him massive confidence going forwards.”
Mignolet moved to Liverpool in a £9m deal from Sunderland under Jurgen Klopp’s predecessor Brendan Rodgers.
The Reds are looking to win the competition for a record ninth time after Liverpool last won the League Cup under Kenny Dalglish in 2012.
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