Liverpool boss Jurgen Klopp admits he's unsure of how long Alexis Mac Allister will remain sidelined.

The midfielder suffered a cut knee in victory over Sheffield United last week.

"It's a bit more tricky than we thought at the first moment," said Klopp.

"The other boy stepped on his knee and the stud went through pretty much the muscle on to the bone.

"Now, we have to wait until the bone is healed and until Macca can deal with the pain, because it is pretty painful.

"Macca is actually a super-tough guy so we have probably to make sure just from an infection point of view nothing happens. That's really important.

"I never had this injury for one of my players before but now we have it.

"I hope it will not take that long, I would like to say it's day by day - but that would look like he could maybe play the next game but he will not be ready for that as well.

"I hope the next three or four days he makes big steps and then we will see."