There was a moment towards the end of this game that summed up just how utterly and comprehensively Saints had beaten Manchester City.
With the score 3-1 and little more than three minutes of normal time remaining, Jack Cork found himself deep in City territory, down by one of the corner flags.
Under pressure from Gael Clichy, he attempted to hit the ball out of play via the leg of the defender, only to see him jump out of the way.
The ball trickled into the area, straight to the feet of Javi Garcia.
The centre half had time and options aplenty. Pass it to Joe Hart, send it out to the wing where Aleksander Kolarov was free, or simply clear it down field.
Instead, he dallied, looked around desperately for help, and turned towards his own goal.
Saints striker Rickie Lambert began bearing down on him from behind and, in a state of either panic or frustration – or both – the £15.8m defender simply booted the ball out of play for a throw in, before chucking an arm up in the air in disgust.
It wasn’t exactly clear whether that was at himself, or his teammates. None of them put up much of a defence, though.
City, by this point, were both mentally and physically beaten.
Saints’ relentless pressing of them throughout the match had simply worn down the Premier League champions.
The style of play employed by Mauricio Pochettino – pressing both constantly and as high up the pitch as possible – completely unsettled their opponents from the very start.
City were never allowed to move the ball out of their half with any ease, and Saints’ opening goal came from Jason Puncheon winning the ball off Gareth Barry in City territory.
Barry will certainly have nightmares about this one.
After Joe Hart’s howler had gifted Saints a 2-0 lead, Barry committed an inexplicable error early in the second half to make it 3-1, nonchalantly stroking Lambert’s tame low cross into the bottom corner of his own net.
Perhaps the relentless press that the home side had utilised preyed on his mind and he simply panicked.
If so, what an endorsement for Saints’ approach.
They turned the champions of England – never easy beasts to unsettle – into a team that looked distinctly average for long spells.
Under the embryonic reign of Pochettino, they have done similar to both Everton and Manchester United.
As the Saints players consistently mention, it is the intense level of pressing that has been the biggest change from the Nigel Adkins’ era.
It is a tactic that Pochettino used to good effect at Espanyol.
His greatest influence, Athletic Bilbao’s revered coach Marcelo Bielsa, is famous for it.
Under Adkins it was not an alien concept. The former boss occasionally spoke of an “attacking-third press”.
Often, though, he would instead utilise his “mid-third” or “defensive-third” press.
Under Pochettino, it is an all-out approach.
Saints swarmed over City so effectively that, at times, their opponents must have wondered if the home side had their entire 18-man matchday squad on the pitch.
The new manager is fortunate in some ways, of course. One, that he took over a team who were playing at a high level and were also very well organised. Two, that he inherited a group of exceptionally fit and hard-working players.
Morgan Schneiderlin’s propensity to run for more than seven miles in a match is just one example of that.
So Pochettino has not had to go searching for the tools necessary to complete the job.
But that should not detract from just how encouraging the opening few performances have been under him.
Hopefully Saints can continue this intense approach under him, and avoid fading.
If so, the climb up the Premier League table only looks likely to continue.
All the latest on Saints in today's Daily Echo