Liverpool will only have three centre-back options for the visit of Sparta Prague in the Europe League, with UEFA red tape ruling out another.
Ibrahima Konate is expected to miss out in midweek despite being seen in light training on Tuesday, with Joel Matip already out for the season with an ACL injury.
And while Konate’s absence was filled by 17-year-old substitute Amara Nallo in Sunday’s 1-1 draw with Man City, that will not be possible against Sparta.
UEFA rules stipulate that players are only eligible to be registered on List B for a Europa League squad if they are age 21 or under and have been on the club’s books for at least two years.
With Nallo a summer signing from West Ham, Liverpool will not be able to register the teenager for the tournament this season.
That is also the case for 16-year-old midfielder Trey Nyoni, who joined the club from Leicester around the same time as Nallo.
It leaves Klopp with only three senior centre-back options in Virgil van Dijk, Joe Gomez and Jarell Quansah, with Gomez more regularly required at full-back.
Van Dijk was absent from training on Tuesday but is not believed to be injured, with a handful of players working individually.
The captain will almost certainly partner Quansah at centre-back again, then, with Gomez either starting in place of Conor Bradley at right-back or on the bench.
Rhys Williams, who has recently returned to action with Liverpool U21s after injury, is not eligible as he is now 23 and would have had needed to be registered for the main Europa League squad.
In fact, the next-most experienced centre-back from the academy who Liverpool could feasibly register to List B is 16-year-old Carter Pinnington.
With Pinnington not part of the squad put through their paces at the AXA Training Centre on Tuesday, the likelihood is that he is not being considered even as emergency cover.
The Reds head into the second leg of their last-16 tie with a resounding 5-1 lead, but still need to get the job done to ensure a place in the quarter-finals.
