Jurgen Klopp has "no clue" whether Virgil van Dijk will be able to overcome illness to feature in Liverpool's Club World Cup final against Flamengo on Saturday.
Van Dijk missed Wednesday's 2-1 semi-final victory over Monterrey, as the Reds needed a stoppage-time winner from substitute Roberto Firmino in Doha.
With Joel Matip and Dejan Lovren already absent through injury, Liverpool deployed captain Jordan Henderson, nominally a central midfielder, in an unfamiliar centre-back berth alongside Joe Gomez.
Those two may have to play together again against Flamengo if Van Dijk cannot return, though Klopp's squad is due to be reinforced by young stars who were beaten 5-0 by Aston Villa in the EFL Cup on Tuesday.
Asked whether Van Dijk would be back for the final, Klopp told BBC Sport: "We have no clue, to be honest.
"We thought when we came here he will be fine for today - he wasn't.
"We'll see, I don't know. We brought now a few kids - Sepp [van den Berg], Ki-Jana Hoever are here, Harvey [Elliott] will come tomorrow. We will see what we can do line up-wise."
Firmino, Trent Alexander-Arnold and Sadio Mane all started Wednesday's semi-final on the bench.
However, after Rogelio Funes Mori cancelled out Naby Keita's opener in the first half, the possibility of extra-time loomed for a Liverpool side already facing a gruelling December fixture list.
Thankfully for Klopp and his side, Alexander-Arnold's 91st-minute cross was swept home by Firmino to seal the victory inside normal time.
Klopp was pleased with the performance and also singled out goalkeeper Alisson for praise after he made a string of saves.
"We controlled the game for long periods of time in the first half," Klopp added.
"We played really well for a line-up which is made to control the game, because we had not a lot of defensive players on the pitch, that's the problem.
"Of course, they had their counter attacks. All you need is Alisson Becker in the end. He must be there and he was there in the decisive moments."