before drawing a booking out of Ignasi Miquel when skinning the Spaniard.
At the other end, the excellent Tom Thorpe and substitute Michele Fornasier made masterful tackles on Thomas Eisfeld and Sanchez Watt respectively but there was relief when Hayden passed up a glorious opportunity to give the hosts the lead by side-footing wide of an inviting target.
Thorpe looped a speculative effort over the top before McGinty was booked for a foul that almost led to further punishment as Henderson beat Gollini with the free-kick but the bar came to United's rescue. It proved to be only a stay of execution as Arsenal dominated the possession in the closing stages and snatched a winner when Bellerin beat Lingard to a loose ball just outside the area and swerved a volley past Gollini.
There was controversy at the death when Bellerin blotted his copybook with a poor challenge on Ekangamene. Incredibly, it was the United scorer who was booked for complaining rather than the adventurous full-back.
United: Gollini; Vermijl, Thorpe, McGinty, Büttner (Fornasier 46); Cole, Veseli, Tunnicliffe, Ekangamene, Lingard; Januzaj. Subs: Blackett, Sutherland, Cofie, Daehli.