Arsenal left St Mary's with all three points gift wrapped thanks largely to a glaring error from Southampton goalkeeper Alex McCarthy.
The Saints stopper was at fault for Arsenal's opening goal after Eddie Nketiah charged down his pass to score. Southampton pressed late on in search of an equaliser, with stand-in keeper Emiliano Martinez superbly denying Shane Long.
But any hopes of a comeback disappeared when Jack Stephens was sent off for a last-man foul on Pierre-Emerick Aubameyang. Joe Willock then doubled Arsenal's advantage from the resultant free-kick, reacting to a rebound off McCarthy to seal the win.
Here are the talking points from St Mary's. 1. Arsenal back to winning ways After a difficult restart Arsenal got back to winning
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