Miss me yet? How Alisson won Liverpool over 13 extra points last season...

The Reds will be without the Brazilian for a number of weeks through injury and he could be a heavy loss based on his statistics from last term

The flipside to Alisson Becker being such a perfect fit for Liverpool is the imperfection left in his absence. The best goalkeepers can generally be relied upon to provide consistent service without needing rest or rotation and the injury suffered by Liverpool’s No. 1 on Friday night throws up a significant problem for Jurgen Klopp.

The manager was putting no timeframe on how long his goalkeeper would be missing but the fact of the matter is that it’s going to be weeks rather than days. Adrian, signed as a back-up after his West Ham contract expired, is a vastly inferior goalkeeper in all aspects to Alisson but will have to come in and deputise nonetheless.

Liverpool’s run to the Champions League title and second place in the Premier League was predicated on a mean defence first and foremost, with only seven conceded in the top flight by the halfway mark last season. They ended up letting in only 22 in all – the best in the league – and have Alisson, Virgil van Dijk and Co. to thank for their sixth European title and record-breaking Premier League points total as much as their much-vaunted front three.

That was thanks in no small part to Alisson’s heroics between the posts. That’s not to say the Copa America winner was flying around his goal every two minutes keeping shots out. Rather, it was that Alisson was there to be depended upon as required.

Liverpool did not give up a lot of shots overall, truth be told, but Alisson saved a better percentage of chances compared to his goalkeeping peers at other clubs. If they give up chances at a similar clip during his absence then it would be only reasonable to deduce that – with a goalkeeper of a lower standard in his place – they are going to concede more goals.

It’s Jurgen Klopp’s worst nightmare; Alisson is perhaps the only true irreplaceable in the Liverpool line-up. They had to do without Van Dijk in the home leg against Bayern in the Champions League last 16 for example and still eased their way to a clean sheet. Mohamed Salah played no part in the second leg of the semi-finals against Barcelona. Other players can come in for those high-profile stars and do a job for the team.

Alisson is probably the only one whose exact attributes match the requirements demanded by his position. And that’s what could well derail a Liverpool title bid over the next few weeks.

They won six games in a row to start last season, conceding only twice, and on occasion last term were a world class save or two from Alisson away from conceding goals that might well have cost them points or progress. A late save from Arek Milk in the final Champions League group stage game against Napoli – which preserved their status in the competition - comes to mind in that context.

Without him there are no guarantees. Across 38 league games last season, Alisson made 76 saves in all from the 307 shots that Liverpool allowed. Fifty of those saves were made from efforts inside the box. Plenty of credit goes to Liverpool’s backline for restricting the number of shots in the first place but the ones that did get through were more often than not repelled by Alisson.

His save percentage was 77, the best in the Premier League, whereas David de Gea – widely regarded as the best goalkeeper in the division - was much further down on 69 per cent.

Ederson – Manchester City’s goalkeeper and Alisson’s national team rival – conceded more goals (23) from fewer shots faced (238). That speaks of Alisson’s ability to make big saves when they matter.

Based on the quality and number of chances that Liverpool gave up last season, they conceded seven fewer goals than their expected goals (xG) projections. That's according to data from Understat. In turn, that helped account for a 13.5 point over-performance in the league, which put them far closer to Manchester City than might have otherwise been expected. Thanks, in no small part, to Alisson's ability to prevent goals one-on-one.

Furthermore, no regular starting goalkeeper played more successful passes than Alisson’s 864 throughout the course of the Premier League season. Liverpool – along with Manchester City and Chelsea – use the goalkeeper like an outfield player more often than any of the other Premier League teams. They do this because it’s fundamental to their play and – therefore - need dependable goalkeepers to pull it off like Ederson and Kepa Arrizabalaga.

The last time Adrian was a regular in the division – when he shared duties with Joe Hart at West Ham – he had only 42.5 per cent passing accuracy and his save percentage was low down at 70 per cent. Those numbers are okay and no better, but probably nowhere near good enough to sustain Liverpool’s brilliance at the back.