Arsenal boss Arsene Wenger admits Thomas Vermaelen has suffered a setback in his recovery from ankle surgery.
The Belgian international was expected to make a first-team return after the international break, but Wenger has revealed that he will now face a longer spell on the sidelines.
Wenger said: "He will be a fraction longer than expected. He will not be straight back after the international break. One or two weeks later and we still have to count one month for him."