The Reds signed Alisson in a world record fee for a goalkeeper last month after Liverpool FC spent £67m on the Brazil international from Serie A giants AS Roma.
The 25-year-old will wear the number 13 shirt after turning down the chance to become Liverpool FC’s new No1 at the expense of German shot stopper Loris Karius.
The former Mainz 05 goalkeeper made two big mistakes in the Champions League final back in May to allow La Liga side Real Madrid ease to a 3-1 win against Liverpool FC.
His back up Simon Mignolet has also struggled to find a level of consistency in the Liverpool FC team under Jurgen Klopp and his predecessor Brendan Rodgers.
Former Liverpool FC defender Carragher believes the arrival of Alisson will provide the Reds with a real boost ahead of a potential title challenge this season.
“Everyone’s talking about Liverpool and with good reason,” Carragher told Sky Sports.
“You look at getting to a Champions League final and having Virgil van Dijk for a full season. We’ve seen the impact he made after arriving in January. The goalkeeping situation has given everybody a massive lift.”
Carragher added: “What happened in the Champions League final with Loris Karius, yes it was disappointing for the Liverpool supporters on the night losing that game, but we’ve all been there as players where you have a poor game. But it’s happened in a game which will, unfortunately, be remembered for a long time.
“Hopefully he will go on to be a great goalkeeper and be remembered for that but Liverpool had to make a change because I think there would be no belief in Liverpool actually, never mind winning a league but challenging for the league with the two goalkeepers they had.”
Liverpool FC have also signed AS Monaco midfielder Fabinho, RB Leipzig star Naby Keita and Stoke City playmaker Xherdan Shaqiri in the summer transfer window.
The Reds finished in fourth place in the Premier League table to ensure a Champions League spot.
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