Liverpool are awaiting the results of a scan to discover the extent of Steven Gerrard's hamstring injury.
The Reds captain came off in the second half of Tuesday's victory over Tottenham after complaining of tightness.
"Unfortunately he felt his hamstring towards the end of the game and he is having a scan this morning and we are just waiting for results to come back," Liverpool assistant manager Colin Pascoe said.
Forward Raheem Sterling missed the midweek game with a foot injury but Pascoe is hopeful he will be fit for the weekend.
"We are monitoring Raheem. He missed a game the other night but we will see how he is," he said.
Pascoe also said there was no indication how serious the injuries were to both players.
"Not at the moment. Hopefully they will be fit for the weekend," he added.
"Hopefully the scans (on Gerrard) won't show too much but as we've not got the results I can't say too much."
Pascoe was standing in for Liverpool manager Brendan Rodgers at a press conference ahead of the FA Cup fifth-round tie at Crystal Palace on Saturday.
"He had to get off sharpish after the game for a meeting in Europe. It is a club matter and none of your business," he said.
Press Association Sport understands Rodgers has been in Italy on player-related business.
