Liverpool have been hit with a severe injury setback after scans confirmed Alisson faces six weeks out with a hamstring injury sustained against Crystal Palace on Saturday.

The Brazil goalkeeper was ­withdrawn in the 79th minute of the 1-0 victory ­having ­sustained a second hamstring pro­blem of the season. Tests have revealed the severity of the injury means Liverpool will be without their first-choice goalkeeper until after the November international break.

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Liverpool face a demanding ­sche­dule between the international breaks in October and November, a period the manager, Arne Slot, believes will show the measure of his Premier League leaders. But they will do so without Alisson, who is expected to miss Premier League games against Chelsea, ­Arsenal, Brighton and Aston Villa, the Carabao Cup trip to Brighton, and ­Champions League group matches against RB ­Leipzig and the German champions, Bayer ­Leverkusen. Should he return on schedule, he would be ­available for the league trip to ­Southampton on 24 November and Real Madrid’s visit to Anfield three days later.

Alisson missed 10 games last ­season because of injury and ­illness and was absent for this season’s league defeat of Bournemouth plus the Carabao Cup rout of West Ham with a hamstring problem. But he remains a hugely influential figure.

Liverpool signed the Georgia ­international Giorgi ­Mamardashvili from Valencia in August in a deal worth up to £29m but he will not move to Merseyside until next ­summer. Caoimhin Kelleher will get another opportunity to impress in Alisson’s absence while the third-choice keeper Vitezslav Jaros, who replaced the South ­American at Selhurst Park with Kelleher sidelined with illness, is highly rated at Liverpool.