Alisson signed a long-term contract with the Reds after undergoing a medical and completing the formalities of his switch at Melwood last night.

Upon putting pen to paper, the Brazil international told Liverpoolfc.com: “I’m really happy, it’s a dream come true to wear such a prestigious shirt for a club of this size that is used to always winning.

“In terms of my life and my career, it’s a huge step for me being part of this club and this family.

“You can be certain that I’ll give my all.”

Alisson, who began his career with Internacional in his homeland, was Brazil’s No.1 at the World Cup in Russia this summer.

Alisson, 25, has signed a six-year contract.

A swift conclusion to the transfer was necessary as Chelsea were interested, but the Blues had to finalise the future of Real Madrid target Thibaut Courtois before they could act and that allowed Liverpool to steal a march on their Premier League rivals.

Reds boss Jurgen Klopp believes he has secured the services of one of the game’s top keepers.

The German said: “At one point in the last few weeks it came up, the opportunity to sign one of the world’s best goalkeepers — then it’s not a long thought, to be honest, it’s only that you need to have a little talk with the owners. They were quite excited, so we did it.

“The full package is just good.

“How we all do, he needs to adapt to the English Premier League, that’s how it is. The league is different, the refs are different, the goalkeeper life is different in the Premier League.

“Of course he still has to adapt and age-wise he can improve, the best years are coming in the goalkeeper life, so it’s all good.”

It is the second major transfer between Liverpool and Roma in 12 months, the Reds having bought Mohamed Salah for what turned out to be a cut-price £38million after the Egypt international scored 44 goals last season.

Roma, under Financial Fair Play pressure at the time, felt they had been short-changed over the Egypt forward and were determined not to be stung twice, but the agreement struck for Alisson is one acceptable to both parties.

The fee can be partly offset by the sale of Wales international goalkeeper Danny Ward to Leicester.

Liverpool have agreed a £12.5m fee with the former Premier League champions plus a 20% sell on clause.

Alisson’s arrival, following on from that of midfielders Naby Keita and Fabinho, and winger Xherdan Shaqiri, is understood to have completed Klopp’s business for the summer.

They have no intention of going back in for Lyon’s France playmaker Nabil Fekir after a move fell through just before the World Cup despite a fee initially being agreed.

Brazilian midfielder Fabinho, who played the second half of last night’s friendly win over Blackburn believes teh club is now ready to win the Premier League title.

The Reds finished 25 points behind City in fourth last term but Fabinho believes they can claim a first top flight title since 1990.

“I believe so,” Fabinhno said yesterday. “I believe we have a very good team and we will be able to fight for the title.

“I understand we have excellent players. We have an excellent manager (Jurgen Klopp). I understand also that City are the champions and last season they produced excellent football. We will do our best to get the title from them and make everyone happy here.”