Danny Welbeck and Theo Walcott run riot against Southampton

 Danny Welbeck scores the opening goal and the first of his two in Arsenal’s easy 5-0 win at Southampton in the fourth round of the FA Cup. Photograph: James Marsh/BPI/Rex/Shutterstock

Arsenal extended their unbeaten start to 2017 as they coasted into the FA Cup fifth round by comfortably disposing of Southampton, with Theo Walcott marking his return from a calf injury by bagging a hat-trick against his former club and Danny Welbeck scoring twice.