Liverpool lost midfielder Fabinho to a hamstring injury in the early stages of Tuesday's trip to Aston Villa.
The Brazilian was the only usual starting midfielder not to be given a rest for the game, starting behind Naby Keita and Curtis Jones, but he didn't look right during his short time on the pitch and was guilty of a number of poor touches.
It was in an attempt to make up for his loss of possession 27 minutes in that Fabinho was seen reaching for his hamstring, with the Brazilian going to ground soon after and limping off after a short chat with the medical staff.
Fabinho will now be sent for further checks to determine the severity of the injury, which could hardly have come at a worse time as Liverpool continue their quest for the quadruple.
Jurgen Klopp's men will face Chelsea in the FA Cup final on Saturday and have a Champions League final with Real Madrid to look forward to on May 28 - either side of two fixtures which will decide their fate in the Premier League title race.
The Reds still have Southampton and Wolves left to play in the league and may well have to navigate those games without Fabinho.
It was Jordan Henderson who replaced the Brazilian against Villa and the veteran midfielder may have to keep that deeper role for the rest of the season.