The 26-year-old Brazilian damaged a calf during the first half of Friday night’s 4-1 Premier League victory over Norwich and while the club has put no timescale on his recovery, Klopp is expecting to have to do without the Champions League winner for some time.
Klopp, whose side meet Chelsea in the UEFA Super Cup on Wednesday, told the club’s official website: “[It’s] Not too cool. It’s a calf injury, which takes him obviously out for a while.
“I don’t want to make now [an] exact prognosis on when he will be back, but it will not be Wednesday for sure, so then we have to see. It takes a while, it takes a couple of weeks for sure, and we have to see.
“I saw already like ‘six weeks’ and stuff like this, but Ali was not a lot injured in his career, so I would like to wait a little bit to see how he develops in that process now, but he is not in for the next few weeks.”
Brazil international Alisson was replaced by summer signing Adrian six minutes before the break in the Norwich game with his side already leading 3-0.
The Spaniard played the remainder of the match and was beaten by Teemu Pukki as the Reds ran out 4-1 winners.
Adrian is now in pole position to keep his place for the Super Cup clash with Premier League rivals and Europa League winners Chelsea in Istanbul, with Irish youngster Caoimhin Kelleher next in line following Simon Mignolet’s departure for Club Brugge.
However, Kelleher is working his way back to full match fitness after recovering from a wrist fracture and Klopp has indicated he will hand a short-term deal to Andy Lonergan.
The 35-year-old, a free agent after being released by Middlesbrough at the end of last season., was part of the squad during pre-season and is still training with the club.
Asked if Lonergan will be on the bench on Wednesday, he replied: “I think so. I didn’t speak to [goalkeeping coach] John [Achterberg] yet about that. We spoke a lot about the goalie situation apart from what we have to do [on Wednesday]!
“We will see, but we can have obviously a lot of players on the bench there, which is good and I think Andy will be one of them.
“He was in with us, he’s a brilliant character, a really nice lad and helped us a lot in the pre-season, and now we (have) decided to work together with him.”
Alisson’s loss for an extended period would represent a blow to the club he joined from Roma in a £65million switch last summer.
The South American played a key role in Liverpool’s title charge, which came up just short, and their European triumph as the decision to invest heavily in a problem position paid off handsomely.
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