Real Sociedad, which must also do without Aihen Munoz (same position), seriously injured in the knee, did not specify the time of unavailability of the 26-year-old left side, on loan since this summer from Arsenal.
He injured the biceps femoris muscle in his left thigh during the Copa del Rey quarter-final against Celta Vigo (2-1 victory). The Scottish international already suffered a hamstring injury at the start of the season and missed several La Liga and Champions League matches.
On Wednesday, the Basque club formalized the arrival of a left back, Javi Galan, from Atlético Madrid. Last week, Union Berlin's Surinamese striker Sheraldo Becker signed to strengthen the San Sebastian team's offensive line.