Liverpool midfielder Thiago Alcantara was not pictured in training with the Reds ahead of Wednesday's Champions League quarter-final second leg with Benfica.
The Spain international lasted 61 minutes of the first-leg win at the Estadio da Luz before lasting the full 90 of the weekend's 2-2 draw with Manchester City in the Premier League.
Jurgen Klopp did not pick up any fresh concerns in the draw with the Citizens and affirmed at his press conference that he expects to be working with a fully-fit squad for the visit of Nelson Verissimo's side.
However, Thiago was nowhere to be seen as Liverpool warmed up for Wednesday's tie at their AXA Training Centre in Kirkby, raising slight doubts over his availability for the midweek game.
Klopp did not have Roberto Firmino at his disposal for Friday's training session, but the Brazilian was still part of the Etihad trip, and all other central midfield options appeared to have been present on Tuesday.
Thiago has struggled to stay fit for the entire 2021-22 season but has managed 27 appearances in all competitions for the Reds, scoring two goals and setting up two more.