Manolo Gabbiadini scored the only goal of the game in the closing stages, with the Saints moving three points clear of the Swans.
Whatever happens in the other midweek games, Swansea will go into the last day still alive, but they are currently three points behind with a goal difference of -27 in comparison to Southampton’s -18.
Things look decidedly grim, especially when considering the fact Cardiff will be enjoying the riches of the Premier League next season, something Swansea will not want to miss out on.
It may be difficult to grasp my tone here, but it is a pretty solemn one.
A display full of heart
It is so often a phrase that comes up; ‘they played with heart’.
Why does it invariably apply to the losers? Carlos Carvalhal’s men knew they needed to put in a strong performance against a side fighting for their lives, and they would need a bit of luck too. However, this eluded them.
As you would expect from a relegation dog-fight, chances were snapped at, passes were misplaced, fingernails were gnawed, and challenges were cynical.
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In the end, the side that rode their luck the most won the points, and Southampton look set for safety, barring a miraculous turn of events on the final day.
Carvalhal has overseen an incredible turnaround this season, but he could not quite summon up one last piece of magic against a side in fairly good form of late.
Every player chased every loose ball, no blade of grass with left untrodden, and legs will now be leaden, but that will be from both fatigue and the weight of the situation they find themselves in.
It is not over yet
Swansea sit on 33 points from 37 games, while Huddersfield have 36 points from their 36 games. The Terriers face games against Chelsea and Arsenal as their season looks set for a rocky finale.
Swansea take on already relegated Stoke and, if they are able to take all three points, they too will sit on 36 points.
If Huddersfield are to lose twice then they will fall behind Swansea - if the Welsh side can win.
It is not the situation the Swans wanted to be in come this point of the season, but it is not one that has seen their season end in relegation before the final game.
Can Swansea escape the jaws of the bottom three? Everyone in Swansea will be watching Chelsea vs Huddersfield with baited breath.