Carlo Ancelotti knew this day would come.

Not necessarily in the meek fashion with which they lost to Southampton here, but he was certain that Everton's unbeaten run would end at some point.

That, in his words, the bubble would burst, eventually.

But he said the real focus would not be in how they lost - although that won't stop some frank discussions being had at Finch Farm this week - but in how they react. How they respond.

So it would not have been long after this loss on the south coast, the first of Everton's season, that Ancelotti's thoughts turned to the north east and next weekend's trip to Newcastle.

Yet in preparing for that game at St James' Park, Ancelotti will have to look at went wrong here because the Everton squad he takes up there could be depleted further than the one that travelled down here.

It will certainly be hurting. It certainly didn't deliver today.

Richarlison remains suspended for next weekend's game and, at this stage, he will be joined on the sidelines by Lucas Digne who was shown a straight red card for treading on the ankle of Kyle Walker-Peters while James Rodriguez finished this miserable afternoon holding his left hamstring, and will be checked.

Everton have still not won a league game when Richarlison has been absent, by the way, and if Ancelotti had hoped Alex Iwobi, and then Bernard who was brought on at half-time, would show they can adequately fill the void, then he was left disappointed.

But there's perhaps a wider issue at large here.

Look, we cannot lose sight of the fact that this is Everton's first defeat in the opening nine league and cup games this season and the Blues remain top of the Premier League table.

It has been a superb start to the campaign and this loss should not distract form that.

The first defeat after such a run was always going to hurt, especially after such a poor performance, but Ancelotti and his players have been excellent. This does not change any of that. The excitement and hope for this squad, under this manager, is there with good reason.

But to bounce back as he, and we, all hope then the manager needs to find a way of tightening things up.

The only clean sheet Everton have kept in the league this season was on the opening weekend of the season at Spurs when, after a couple of fine Jordan Pickford saves to ensure it stayed 0-0, they kept Jose Mourinho's side at arm's length and should have won by a greater margin, such was their dominance.

Since then, in the league, the Blues have conceded twice against West Brom, once at Palace, twice at home to Brighton (albeit one came in time added on), twice against Liverpool and twice more here.

As scintillating as Everton's attack has been, the laws of averages over the course of a season say there will be more games like this one to come.

More games where there is no Richarlison (he definitely misses the next two), where Dominic Calvert-Lewin, who is used to having minimal touches but at least expects quality service, is isolated and marshalled well and where Rodriguez cannot unlock a defence, however much he tries.

Digne's absence, unless Everton appeal as Ancelotti says, is another attacking outlet which the manager will be without in the near future and there will be games when, as was the case today, the support cast and those given a chance to impress, don't deliver.

It can't always be expected that the Blues out-score the opponents in the way they have done so far.

We have hailed their resilience, that ability to respond to in-game set-backs and return fire, but it didn’t happen today and can’t always be a given, each and every week.  There will have to times, like at Spurs, where they take a lead and protect it.

Everton have to find a way of being hard to play against.

A 1-0 at Newcastle in a week's time could be just what the doctor ordered.

Southampton are a good team, make no mistake, but there was an ease in which they scored their two goals, inside eight first-half minutes, which will concern Ancelotti.

He has to expect his players to be tougher to get at than they were today.

Sure, he may point to the fact that Southampton, despite finishing with a man extra and being the better side for long spells, still only had six shots on target, but by half-time the damage was done and the home side were happy to sit in and soak up Everton's second-half pressure.

We've rightly, praised the performances of Michael Keane and Yerry Mina of late, Everton's midfield has been revamped with Allan and Abdoulaye Doucoure and yet, clean sheets are hard to come by. Everton's spine has not looked as strong in years, but teams can still get at them.

Is it a by-product of playing 4-3-3, a formation that has (before today) unlocked Everton's attacking potential with 14 goals in the league, that the Blues will be more susceptible than if, for example, they played in the 4-4-2 system the manager employed earlier in his reign?

Maybe.

Depending on personnel, Ancelotti may consider tweaking the system for next weekend. Teenager Niels Nkounkou, though very highly thought of and having performed so well in the cup, is now in line to make his league debut at Newcastle, and so Ancelotti may feel the need to play a formation that offers him some protection.

But, of course, it depends how those either side of the spine play, or if they are available to.

Gylfi Sigurdsson, Alex Iwobi and Bernard failed to take their opportunity to impress and will consider themselves fortunate if given another chance next weekend.

Andre Gomes, you expect, will come back in or maybe Fabian Delph who did fairly well when introduced. There may also be a chance, from the start, for Anthony Gordon.

Either way, it feels imperative that Ancelotti not only picks the side that will produce the reaction he is looking for after this, a first defeat of the season, but one that is hard to play against.

A clean sheet is overdue.