Saints are a team of ever changing style.
Maybe it has been borne out of necessity for manager Claude Puel, maybe it has been a learning experience for the Frenchman in his first season in the Premier League.
Whatever it is, the side is becoming increasingly unrecognisable from the first part of the campaign.
Slightly in terms of personnel, and certainly in terms of the way they are playing, their philosophy towards the game, and that all important and much debated entertainment factor.
In the first half of the season the general thought was that Saints were a little dull. They sat deep, gave very little away defensively, but could rarely have been accused of being an expansive attacking side.
It might have been the number of games that forced Puel into a style and formation that produced that way of playing.
Perhaps the current reversal could in part be due to the fact that Virgil van Dijk and Jose Fonte are no longer at the heart of the defence for very different reasons, and a deadly striker in Manolo Gabbiadini has been recruited to lead the line.
Perhaps those things are mere coincidence, and Puel has simply shifted his mind-set as he gets to grips with the division.
What is beyond doubt is that Saints have transformed.
They are a team whose games are now value for money.
They do concede, but they do also press forward.
They are liable to blips, as we saw in the first half at White Hart Lane, but can also be strong and stirring, as we saw in the second half at White Hart Lane.
It really was a first half to forget for Saints.
Losing their talisman and trailing by two goals at the break was about as bad as you might have feared it could be.
Knowing Tottenham would want to play out from the back Saints tried to press them high.
However, they were up against a very strong side who are second in the table for good reason.
And with Saints’ current vulnerabilities at the back, Spurs always felt they were in with a chance whenever they attacked.
They fired a warning shot after just three minutes as Christian Eriksen played a ball round the outside to Heung-Min Son but Fraser Forster was quick off his line to charge down the danger.
The Saints stopper was left clawing at air on 14 minutes as Spurs took the lead.
For all the talk of Harry Kane being out, Spurs didn’t really miss him with Eriksen in particular such a handful to pick up between the lines.
He found himself in a bit of space in the pocket and needed just a yard and a flash of inspiration to measure a left footed shot into the bottom corner to give his side the lead.
Dele Alli made a poor connection as he turned in the area to try and double the Spurs advantage, while Forster scooped away Toby Alderweireld’s flicked header from a corner.
Saints’ pressing did make them occasionally dangerous and they had a hat-trick of chances which might have yielded more.
Oriol Romeu was unlucky with a half volley from distance that curled just off target, while Tadic and Gabbiadini combined for the Italian to hit the side netting too, but it came at price with the striker hobbling off injured.
Tadic should have done much better with a first time strike from just outside the six yard box, under little pressure after Nathan Redmond’s deft touch back to him which he may or may have quite kept in play.
But, that having been and gone, the game took a decisive swing just moments later.
With Saints down to ten and unable to get Shane Long on to replace the departed Gabbiadini, Spurs won a penalty.
Saints couldn’t hack the ball away as it cannoned around, Steven Davis lunged in to try and win it and Alli went down just inside the area.
It looked a bit soft, but Andre Marriner pointed to the spot and Alli dispatched it low down the middle.
However, the ref – who also took charge of the EFL Cup final, including that controversial early moment which denied Gabbiadini an opening goal - turned down a strong looking appeal for Saints in stoppage time as Tadic was felled by a clumsy challenge from Ben Davies.
It might have made all the difference too as Saints did find a goal seven minutes after the restart.
Ryan Bertrand was the chief architect with a stunning cross from the left wing which saw two Spurs defenders unable to clear their lines.
It came all the way through to James Ward-Prowse and the man of the moment, fresh from his England call-up, controlled with his midriff and then clinically buried a shot at the near post.
Saints were really up for the challenge and, despite having got into a position where they had a difficult job to get anything from the game, they gave it a good go.
They pinned Tottenham back to the point where Mauricio Pochettino took off Son for Harry Winks with a reasonable chunk of the game to go just to try and shore things up.
Saints, driven on by Romeu, whose central midfield battle with his former teammate Victor Wanyama was a heavyweight clash to behold, pushed them all the way.
Forster had a late save to make as Spurs hit forward on the counter attack, and kept out Vincent Janssen’s stinging near post drive, but it was Saints asking all the questions, and in the end Spurs were delighted to hear the final whistle.
Saints may be mired in midtable, but the development of the team, and their style, is reason for optimism if Puel continues to develop it this way for the remainder of the season.