The unheralded star crucial to Liverpool's hopes this season

This summer at Anfield hasn't gone quite as many Liverpool fans would have hoped or expected.

After a forgettable season where the team failed to challenge for the Premier League or even secure a top-four spot, a major overhaul was anticipated at the Merseyside club.

Initially, there were promising signs. However, players like Roberto Firmino, James Milner, Naby Keita, and Alex Oxlade-Chamberlain left on free transfers, that was pre-planned.

And Liverpool moved quickly to add reinforcements in the forms of Alexis Mac Allister from Brighton and Dominik Szoboszlai from RB Leipzig.

However, the situation took an unexpected turn when substantial offers came in for midfielders Fabinho and Jordan Henderson.

Deemed too good to turn down, the club decided to accept these offers, with Fabinho reuniting with Nuno Espirito Santo at Al-Ittihad and club captain Henderson jetting off to play under his former teammate Steven Gerrard at Al-Ettifaq.

These departures will undoubtedly have a significant impact on the team. Klopp has lost his primary defensive midfielder, arguably his second-best player in that position, and considering Milner's departure, his third-best as well.

This issue is amplified by the fact that the Reds look as vulnerable as we’ve seen them for several years in the centre of their defence.

While Ibrahima Konate is expected to become a key pillar in Liverpool's defence in the seasons to come, there are concerns involving the players around him.

Virgil van Dijk, hasn't shown the same extraordinary levels he consistently displayed earlier in his Liverpool career. Joel Matip - inconveniently entering the last 12 months of his contract - is also on the wrong side of 30 and too often shows his age.

Meanwhile, Joe Gomez has struggled to maintain consistency when given opportunities.

In May, Klopp admitted that he was looking to bring in at least one new central defender this summer.

However, thus far, the club has failed to secure the reinforcements it needs.

The fact that Liverpool have conceded ten goals in their last four pre-season matches should serve as a warning sign for the challenges that lie ahead.

Amidst the departure of key players and increasing vulnerabilities across the team, goalkeeper Alisson Becker's role is poised to become more crucial than ever if the Reds aim of regaining a coveted Champions League spot, which is the minimum expectation at Anfield, is to be achieved.

Since his arrival in 2018, Alisson has been an instrumental part of Liverpool’s success. Even last season, he was one of the few Reds players who consistently managed to operate at an elite level.

Only David De Gea (17) managed more Premier League clean sheets than the Brazilian (14) last season.

And while he might have missed out on the Premier League Golden Glove to his former Manchester United rival, a delve into the underlying numbers highlights how the Liverpool No.1 was not only better than him but also all of his Premier League peers, too.

We can highlight this by looking at Opta’s Post-Shot Expected Goal (PSxG) data. A reminder that PSxG is similar to regular xG but with a difference.

xG is a metric that determines just how good a shooting opportunity is, considering a range of factors, including the distance from the goal, the angle of the shot, the pace of the effort and how it was assisted.

This is done by utilising historical shot data, with 0.01 being the lowest shot value, and 0.99 the highest.

PSxG, though, analyses the quality of the finish from the shooter by taking into account the shot's placement in the goal.

If the effort goes wide or over, the PSxG is zero. This makes it the best current metric for analysing a goalkeeper’s performance from a shot-stopping perspective.

Notably last season, Alisson racked up an overperformance of +10.1. In layman's terms, that effectively means that thanks to his form, Liverpool conceded 10 fewer goals than would have been expected.

That was the best overperformance in the Premier League, and for comparison, it’s worth noting Golden Glove winner De Gea finished with an underperformance of -0.7.

While things are far from perfect for Liverpool going into this new season, the team do still boast a ton of attacking talent meaning they’re well-equipped to score plenty of goals this year.

That will go some way to helping them fight at the top end of the Premier League table.

However, it’s looking likely that they’ll be relying on Alisson to reproduce the form he showed across the bulk of last season if they’re to once again threaten the division’s elite and crucially, break back into the top four.