Substitute Charlie Austin late goal for Southampton was enough to put an end to Arsenal’s unbeating run, in new Austrian manager Ralph Hasenhuettl’s first home game on Sunday.
It was the Londoners’ first defeat in 23 games and meant they lost ground on fourth-placed Chelsea, while Southampton moved out of the English Premier League (EPL) bottom three.
Crosses by Matt Targett and Nathan Redmond was headed in by Danny Ings who is just returning from injury to give the gunner a two goals cushion.
In between, Mkhitaryan drew Arsenal level with a header of his own and early in the second half he scored via a big deflection.
Yet in the 85th minute Austin, who had come on for the tiring Ings, headed in a cross by Shane Long.
Arsenal, who had last lost to Chelsea in the English Premier League in August, remained fifth in the table.
Southampton went ahead again, however, before the interval, with Redmond supplying the chance with a neat chip and once again Ings eluding his marker to score.
Long, replacing Redmond, had a goal rightly disallowed for offside, but he then picked out Austin with a cross that goalkeeper Bernd Leno failed to deal with.
“As a club we know the position we’ve put ourselves, and with the squad we’ve got it’s not good enough,” said Ings.
“But if we keep showing resilience and hard work we can turn it round. It shows we’re moving in the right direction already.”
Arsenal’s Alex Iwobi said his side had not concentrated sufficiently and not defended well enough as a team.
“We’re frustrated the unbeaten run is over,” he added.
“We had chances to win the game. But we should give ourselves some credit for going on the run.”(