Liverpool midfielder Alexis Mac Allister's injury "doesn't look good", said Reds boss Jurgen Klopp.
He carried on playing but was substituted after 57 minutes and later had his wound stitched up.
"Macca doesn't look good, so we have to see day by day," said Klopp ahead of Saturday's trip to Crystal Palace (12:30 GMT).
"They were pretty hopeful after the game that it was not serious. It's not that serious, but in the period of the year if you are out for five days, it's 12 games pretty much."
Klopp added: "I don't expect him to be ready for [Saturday].