• Defender has operation on cruciate ligament in left knee• Leipzig’s Dayot Upamecano on
Arsenal shopping listCalum Chambers has had knee surgery and will be out for six to nine months – an absence that will force Arsenal’s hand in the transfer window.

The centre-back was injured in the first half of Arsenal’s defeat by
Chelsea on 29 December and had surgery on Thursday to repair the ruptured anterior cruciate ligament in his left knee. Chambers will miss the rest of the season and defensive reinforcements this month have now become a priority.