Liverpool had one weakness. One glaring weakness that doomed it in May in Kiev, and that, had it remained, might have preempted a 2018-19 Premier League title challenge. On Thursday, the Reds officially addressed it.

Liverpool announced the signing of Roma goalkeeper Alisson Becker for $72.8 million, the most expensive deal for a goalkeeper in the history of the sport. Roma confirmed that performance-based incentives could spike the fee to $84.5 million. The Brazilian has signed a five-year contract.

And now that he has, he’s filled that gaping hole – and might just have made Liverpool a legitimate contender for Manchester City’s Premier League throne.

Who is Alisson?

The former Roma No. 1 is the ideal Liverpool signing. After just two seasons in Europe, he’s already among the top 10 goalkeepers in the world. And he’s only 25. If anything, he’s still getting better.

He’s also Brazil’s No. 1, consistently selected ahead of Manchester City keeper Ederson. He started every game at the World Cup. His skill set is comprehensive. He’s big (6-foot-4), agile, alert and very comfortable with the ball at his feet. He’s not on David De Gea’s level – at least not yet – but he’s everything Liverpool could want in a keeper. And perhaps most importantly, he’s many things Loris Karius and Simon Mignolet weren’t.

Why Alisson makes Liverpool a contender

Goalkeeping has been a weakness for Liverpool ever since Pepe Reina departed Anfield in 2013. Mignolet was brought in as a replacement. His performance fluctuated wildly, often in a bad way. The next embarrassing error always seemed to be on the horizon.

Karius arrived in May of 2016, at the beginning of Jurgen Klopp’s first summer in charge, to push Mignolet. But he was a $6 million signing – not one expected to grasp the No. 1 shirt and run with it. He did what he was supposed to do, and eventually unseated Mignolet last season. But he had his flaws, too. They were more evident than ever in the Champions League final.

But the position had been problematic for Liverpool all season. The front three were fearsome. The midfield, through lacking technical ability, jelled and fueled Klopp’s press. The January signing of Virgil van Dijk shored up a shoddy back line. Goalkeeper remained a weakness on an increasingly short list of them.

Now it no longer is. Liverpool had underperformed its Expected Goals allowed at least four years in a row. Alisson conceded just 28 goals on roughly 38 xGA last season. That’s a very imperfect way to assess his potential impact. But its a hint.

Alisson will be Liverpool’s fourth signing of the summer. Naby Keita comes in from RB Leipzig as the quintessential Klopp midfield engine. Fabinho has been brought in from Monaco as a versatile ball-winning midfielder behind him. Xherdan Shaqiri will add depth to the attack.

Liverpool, over the latter half of last season, inspired dreams of a 2018-19 title challenge. Its summer business has put itself in position for one. Manchester City, coming off a rampant, record-breaking campaign, is still the clear favorite. But Alisson brings the Reds closer to the Premier League summit than ever before under Klopp.

Alisson becomes the most expensive goalkeeper ever

The $72.8 million, even before the bonuses, is by far the largest fee ever paid for a goalkeeper. The previous records were Man City’s move for Ederson last year and Juventus’ purchase of Gianluigi Buffon in 2001, depending on currencies and exchange rates. The Ederson deal was worth $46.6 million.

The Alisson deal will blow that away, and with good reason. He is a far more known quantity, having helped Roma to a top-four Serie A finish and Champions League semifinal run in his first year as a full-time starter in Europe. Very few world-class goalkeepers change teams at the beginning of their primes, having already proven themselves at the top level. Alisson is doing that, and completing Liverpool in the process.

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Henry Bushnell covers global soccer for Yahoo Sports. Have a tip? Question? Comment? Email him at henrydbushnell@gmail.com, or follow him on Twitter @HenryBushnell, and on Facebook.

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