Saints defensive frailties were finally exposed by a team that knew how to finish it's chances as Claude Puel got his tactics badly wrong.
I have always maintained that the time for judging Claude Puel was at the end of the season and certainly not with four games gone as some did, however in recent matches the French manager has shown a tactical naivety that is worrying.
Once again Puel started with Yoshida and Stephens in the centre of defence choosing to hope that City would be as wasteful in front of goal as Bournemouth, Palace and West Brom where, but Manchester City were of course another story and could easily have doubled their total.
But it was not just in this area that Puel got it totally wrong, bringing Steven Davis back into the team was a given and the club captain was arguably Saints best player, but dropping Jordy Clasie who had been outstanding at West Brom for hm was clearly a mistake.
Likewise up front, I felt before the game that Gabbiadini would have been better used off the bench and I still feel that now.
But perhaps the most baffling tactical gaffe was the third substitution, post match it is being claimed that Shane Long came off because of confusion over whether he was injured or not, either way it was something that should not have happened.
But at that stage of the game 3-0 down with only 8 minutes left, surely this would have been the ideal opportunity to give Martin Caceres a taste of first team action, let him get the pace of the Premier league but more importantly give the manager a chance to assess him in a competitive game.
Even taking Long off this should have been the case, to be blunt we were never going to get three goals back, but at this stageit looked like we might concede a couple more with our defence in disarray.
In truth in a game when we were being over run in midfield taking JWP off upset our balance as it did against Bournemouth, suddenly we had four attacking players on the pitch and only two holding midfield players, we lacked direction and City were soon swamping us and catching us on the break, we were running around like a Sunday morning side with no shape.
Puel's one tactic seemed to be lets try to batter their goal ad hope that they don't break and score which of course now looks a little naive given that City thrive on quick breaks and have the players to use that to the full.
So sad to say that in the past few games Claude Puel is doing nothing to suggest that he is tactically up to the job, when he was being lambasted for his rotation policy in the first half of the season, it looked like it was that which was losing us games, but now it looks a little deeper than that.
Saints squad is good enough to win games whoever is in charge, however it is games lke this that you need a little more from your manager and he does not appear to be able to be pro active and change things when needed.
Of late injuries and suspensions aside he seems content to play the same players week in week out and hope that it works, I know I harp on about it but in each of the last three games we have got points due to the wasteful finishing of the teams we were playing, Im sorry for those that think Yoshida and Jack Stephens are the future of our defence, but as good as they have been in recent games, the fact is that they still kept on being caught out, the fact that the opposition didn't punish us as it should have does not make that fact alright.
Ask yourself would Van Dijk, Fonte, Alderweireld or Lovren been outjumped like that on our first goal, we all know the answer, this is the difference between winning games and losing, you have to concentrate for every minute and be tight at key moments, 89 minutes worth of good work can all be undone if you are not.
Claude Puel needs to show that he can see where we are weak, he needs to show that he knows what to do about it and how to change it to make sure it doesn't happen before it happens.
The jury has always been out on Puel, I have at times seemed like a lone voice defending him and saying give him time, that time is fast approaching it's end and at the moment there is something not quite right !