Thursday night's 4-0 Europa League win over LASK seemed to be exactly the confidence boost that Liverpool's second-choice goalkeeper Caoimhín Kelleher needed. With Alisson facing a spell on the sidelines after sustaining an injury late in the 1-1 Premier League draw with Manchester City, Kelleher knew that he was set for a rare stint in the Reds goal.

The Irishman kept a clean sheet against the Austrian outfit, but he had to work for it, making three strong saves. His distribution was excellent too as he completed 39 of his 46 passes, and 11 of his 16 long balls.

Jürgen Klopp had said in his pre-match press conference that he was hopeful Alisson would return for the clash with Manchester United midway through the month, ruling him out for the Premier League games against Fulham, Sheffield United and Crystal Palace as well as the Europa League meetings with LASK and Union SG. While he's arguably Liverpool's most important player, the schedule did at least make the setback look manageable.

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Kelleher wasn't enjoying his finest season, so his commanding performance on Thursday offered some reassurance for the stretch of games to come. "We see him every day in training, he is an exceptional talent," Klopp said after the game (via Sky Sports). "He is in general a focused person and you will not see him in a bar celebrating the clean sheet. It is a situation [Alisson's injury] we did not want to have but obviously somehow yes because you want opportunities and now he will get a few games and I trust him."

Klopp believes that Kelleher shares many key attributes with Liverpool's number one, while obviously being a couple of levels below as a final product. He's previously billed him 'the blonde Ali', which explains his unwavering confidence in the 25-year-old.

On Sunday, however, the Reds undoubtedly suffered in the absence of the Brazilian. With Liverpool 2-1 up in first-half stoppage time, Kenny Tete diverted Raúl Jiménez's flick-on goalwards, and Kelleher completely misjudged it, scrambling in vain to keep the ball out of the net after it struck him and bounced over the line. Even beyond that, the data suggests it was a weak shot-stopping force as he conceded three goals against a post-shot xG of 1.78.

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Liverpool manager Jürgen Klopp.

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While Klopp would argue that Liverpool's outfielders needed to do a much better job of protecting their goal — Kelleher was left exposed by arguably the Reds' poorest defensive display all season — this is precisely where Alisson proves his worth, having bailed his side out countless times both this season and in years past.

Kelleher's struggle ultimately proved to be a footnote after Trent Alexander-Arnold scored a remarkable late winner in a seven-goal epic, but Liverpool fans will have concerns over the stand-in stopper in the next couple of games. He knows, and Klopp knows, that he's a far better goalkeeper than he showed on Sunday, and he has the chance to prove that before Alisson returns. Ultimately, these could be the matches that define his career outlook, with potential suitors sure to be watching closely.