The real Champions League starts now, and potential fall-out from almost every tie reminds us this is football’s elite

There is so much on the line for clubs, even where this appears to be a shot in the dark, that repercussions will shape the next 18 months of European football

After a long break, a distinctive split in the Champions League has only become more defined, but it is not the one that is usually lamented. It might well be someway linked to the financial landscape of the European game, sure, but what is different here is that the split is between the biggest clubs. It is also a situation that the competition’s last 16 hasn’t really seen before.

Of the 10 big clubs that would be realistically seen as potential winners this season, four of them are respectively seven, 11, 13 and 18 points clear at the top of their domestic leagues. The obvious consequence of that, then, is that as many as five teams are between 13 and 20 points behind.

The situation could actually be worse except one of the leagues that is usually so predictable has become properly competitive, as seemingly eternal Serie A champions Juventus are a point behind Napoli. That exertion is one reason why Napoli are no longer in the Champions League, but also points to a potential effect on the competition and how the rigours of domestic races can influence it.

This distinctive split could further distort the last 16.

It has already distorted the very meaning of the trophy this season for all the main candidates bar Juventus. The European Cup will either represent the culmination that completes a historic season, or the last stand that completely saves a bad one.

Normal football logic would indicate that one of those runaway leaders - Barcelona, Paris Saint-Germain, Manchester City or Bayern Munich - should win the Champions League this season, but then the very nature of a knock-out competition allows sides to more readily defy normal football logic. The most brilliant of campaigns can be undone on one bad night, or from one great performance from otherwise under-performing opposition.

This is now what some of Europe’s biggest clubs and figures are banking on. It is what Real Madrid, Manchester United, Chelsea, Antonio Conte and Jose Mourinho have made the season’s priority. With their domestic leagues out of sight, they are willing to throw their energy into European ties. That also reflects how there are no guarantees here.

When they come up against teams running away with their leagues, they will be the sides with everything to play for, with everything that entails. One big question is whether it is better for your Champions League challenge if you are involved in a close domestic race, as it maintains your edge. The flip side is that it can sap your energy.

This did become a particularly pointed discussion when the Champions League fully expanded to 32 teams in 1999-2000, and led to a temporary trend. With the big clubs still adapting to much tougher schedules but not yet reaping the financial rewards and bigger squads that would come from it, the knock-out stages did, for a time, suit sides who were domestic also-rans. It was in that period won by:

• a Real Madrid who finished fifth in Spain and seven points behind the champions
• a Real Madrid who finished third in Spain and eight points behind
• an AC Milan who finished third in Italy and 11 points behind
• an ‘outsider’ winner in FC Porto
• a Liverpool who finished fifth in England and 37 points behind
• an AC Milan who finished fourth and 36 points behind, albeit with eight deducted because of Calciopoli.

They were six champions, in other words, that defied the usual logic. The connected rise of the ‘super-clubs’ due to the resources accrued from the modern Champions League eroded this and restored an order, to the point now that the trophy has not left La Liga in four years.

The Spanish title races have all gone right to the wire in that period, but such factors have really just been irrelevant next to the fact that one of Barcelona or - more regularly - Real Madrid have just been too good; too big; too super-powered.

That might well be the case again this season since Barcelona have defied so much of the talk after the sale of Neymar, to avoid defeat in the league or Champions League and thereby develop into the stand-out side.

That still might not be as important as the effects of the stand-out tie.

Because, at the centre of this split and many of the discussions is the centre-piece match-up: Real Madrid vs PSG.

Even aside from the fact that one of the favourites will definitely be out, it also brings in so many of the crux issues from that split, and could hint at what way they - and the competition - will go.

On one side, there’s Real, who are 17 points behind their domestic league’s leaders, completely relying on the Champions League but also represent one of the traditional European powers with that profile only deepened with their status as defending champions.

On the other side, there’s PSG, who are again running away with their domestic league, but also obsessed with finally winning the Champions League for the first time as they represent a new petro-funded power bloc with Manchester City.

A PSG victory could well assert a new reality, and represent the rubicon of a new era in the way we’ve seen with big results in the past.

A Real victory, however, could well reawaken the quality players they do have in a way we’ve seen just as much throughout that past.

The winner of the competition may not necessarily come out of this tie, but the winner may well have to play that team. It could condition so much.

This is the other aspect of the last 16 as a whole. If the fact that it is diluted by some smaller clubs and (notionally) one-sided ties means it can be considered an extension of the group stage’s “phoney war” rather than when the competition starts for real, it will set the stage, get the pieces on the board. Clubs like Liverpool, City and United meanwhile shouldn’t take their respective ties against Porto, Basel and Sevilla for granted. United - like Chelsea - do seem to have hit bad form at just the wrong time, City have bad injuries at just the wrong time, Liverpool don’t have the right piece to replace Philippe Coutinho at the most testing stage of the season. Spurs meanwhile have the wrong opposition in Juventus, but it does feel like they may have the most tactical variety for Europe of all the English clubs bar City.

These are the kind of intangibles that condition every competition, but the suddenness of knock-out football can inflate their influence.

It can cause a few further splits in this Champions League than the one that already exists.`