Giovanni Leoni faces a lengthy spell out after sustaining a serious knee injury on his Liverpool debut against Southampton.
The 18-year-old, a £26m summer signing from Parma, impressed before going down awkwardly in the 81st minute.
He was stretchered off in clear pain and replaced by Milos Kerkez.
Liverpool have not confirmed a recovery timescale, with Arne Slot expected to give an update on Friday.
However, medical staff fear the Italian defender could be sidelined for several months, a major setback after his first senior Italy call-up earlier this month.
His absence leaves Liverpool with only Virgil van Dijk, Ibrahima Konaté, and Joe Gomez as senior centre-back options heading into Saturday’s trip to Crystal Palace.
Wataru Endo and Ryan Gravenberch may also be considered as emergency cover.
The injury comes weeks after Liverpool’s failed £35m move for Marc Guehi collapsed on deadline day when Crystal Palace could not secure a replacement.
Speaking in his post-match press conference on Tuesday night, Arne Slot said of Leoni: “He’s down because for him it didn’t feel good immediately.
“But this is something now we have to assess and normally these things don’t happen in five to 10 minutes, you have to wait until tomorrow to see how he comes in and then maybe do an MRI scan to know more.
“Normally the emotions of a player tell you a lot, I saw a player in the Dutch Eredivisie at the weekend who went out completely in tears and it proved to be that he was right (that he had suffered a bad injury).
“But let’s hope for the best.
Giovanni Leoni has expressed his gratitude to Liverpool supporters for their backing after he was stretchered off during Tuesday night’s clash with Southampton.
Taking to social media to address fans on Wednesday, Leoni wrote: “I want to sincerely thank every single person who has shown me support in this difficult moment.
“It wasn’t the debut I had always dreamed of, but I will give everything to be back playing in this magical stadium as soon as possible.
“Thank you so much!”
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