Liverpool are waiting to discover the extent of Jeremy Jacquet's fitness issue after the centre-back was left out of France's Nations League win over Belgium.
The defender had played the previous two matches, his first for the senior team, but was omitted from Zinedine Zidane's squad for Monday's 4-1 victory.
A statement from the French Football Federation said the 21-year-old had sustained a "strain to his left hamstring," while in his post-match press conference Zidane said Jacquet was "slightly injured."
Jacquet has featured in all seven matches for Liverpool this season, starting six alongside Virgil van Dijk in central defence.
Head coach Andoni Iraola has cover in the form of on-loan Barcelona defender Ronald Araújo and Joe Gomez, but Jacquet's potential absence for Sunday's visit of Manchester City would be a significant blow.
The Reds already have doubts over forwards Alexander Isak and Cody Gakpo, whose international exploits with Sweden and the Netherlands respectively were cut short.
Isak was sent home after just one match due to a minor thigh problem, with Gakpo more of a concern after injuring his ankle.
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Their absence would leave Iraola short of options up front ahead of the high-profile visit of City, playing their first match since an independent commission found the club guilty of the vast majority of charges relating to financial breaches.
Summer signing Bradley Barcola could be pressed into action in a central role, even though he is more comfortable out wide, while Florian Wirtz could be moved further forward from his number 10 position.