Antolin Alcaraz 1-og, Seamus Coleman 31-og)
Everton went to St Mary's Stadium yesterday expecting a tough assignment.
What they didn't expect, though, were two moments of madness that possibly dealt a fatal blow to their Champions League qualification chances.
Two first-half own goals - one by Antolin Alcaraz in the the opening minute and the other by Seamus Coleman just after the half-hour mark - left them with too tall a mountain to climb.
The 2-0 defeat by Southampton leaves them needing a miracle to join Liverpool, Chelsea and Manchester City in Europe's elite club competition next season.
Arsenal will rub their hands with glee. The Gunners can go four points clear of the Toffees if they beat Newcastle on Tuesday morning (Singapore time).
Knocked out of the top-four positions not too long ago, the Gunners now need six points from their remaining three games to be certain of a Champions League spot.
Everton manager Roberto Martinez will rue the inexplicable mistakes that were so uncharacteristic of his side this season.
That the first came so early in the game was a massive setback for the away side.
Alcaraz, deployed in the centre of defence because of injuries to Sylvain Distin and Phil Jagielka, could only hide his face in the turf after his worst nightmare came true.