Arsenal fear Kieran Tierney will be out for a number of weeks in a second major defensive setback for Mikel Arteta.
Centre-back David Luiz is set for an extended spell out after undergoing minor surgery on his right knee on Sunday.
And he is poised to be joined on the sidelines by first-choice left-back Tierney who was forced off during Arsenal’s eventual 3-0 defeat against Liverpool on Saturday.
Tierney hurt himself in a clash with James Milner and had to be withdrawn just before half-time after treatment.