Alisson injury update: Jurgen Klopp says star goalkeeper suffered 'proper muscle injury'

Liverpool have lost star goalkeeper Alisson to a hamstring injury and Jurgen Klopp has admitted he doesn't know how long the Brazilian will be out for.

But he won't be back soon and that's a big blow.

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Alisson suffered the injury in training ahead of Liverpool's trip to Brentford on Feb. 17 as the Premier League leaders were without him the weekend before that due to illness.

Young Irish goalkeeper Caoimhin Kelleher has been standing in for Alisson and has done a remarkable job.

Latest Alisson injury update

Speaking to reporters ahead of their game against Nottingham Forest on Saturday, Klopp gave the following update which suggests Alisson will still be out for quite a while.

"There is no real timescale on it, but it is a proper muscle injury," Klopp said. "Different players recover differently. That is it pretty much.

"It is not a sure one. It is not that he will be in contention for next week or something like that. We have to wait a few more weeks, definitely, for him. He is working in the gym, not on the pitch."

What games could Alisson miss?

Kelleher has stepped in admirably to star in Liverpool's League Cup final win against Chelsea and their FA Cup last 16 win against Southampton, as the Irish goalkeeper has now started five-straight games in all competitions for the Reds.

Their next games are a trip to Nottingham Forest, then a massive game at home against Manchester City on March 10 which is sandwiched in-between their Europa League last 16 ties with Sparta Prague. An FA Cup quarterfinal at Manchester United is then the final game before the international break which begins on March 18.

It seems very unlikely that Klopp will have Alisson back fit for that mammoth game against City next weekend, so all eyes are on Kelleher as the young goalkeeper must continue his stunning form as Liverpool push to win all four trophies still available to them in Klopp's final few months in charge.