THE European challenge once existed solely on the football pitch.
Now it lies both in finance and, of course, geography. The elevation of Peter Lawwell, the chief executive of Celtic, to the executive board of the European Club Association may be seen by some as a piece of tedious business in an arcane society.
However, the ECA is increasingly becoming a story. Lawwell's willingness to become a central part of that unfolding narrative is a sign of both the problems clubs face in Europe and their determination to meet them.
So what is the ECA? It is the reconstituted G14 and has 214 club members from 53 associations in Europe. Ordinary membership is based on a country's ranking. In Scotland, Celtic and Motherwell are ordinary members and Aberdeen, Hearts and Rangers are associate members.
The association has a list of objectives that are as vague and unthreatening as a beauty contestant's ambition to have world peace and see the end of poverty. They speak of promoting and safeguarding the interest of European club football and fostering the exchange of information and expertise between clubs. These are innocuous and hardly point to a revolution in European football.
However, there are shifting sands on the continent. Lawwell will be part of how they are eventually shaped. His comment on election to the ECA was straightforward. "There are huge challenges ahead for European football, but we are ready to take these challenges and find solutions," he said.
The major problem, of course, in European football is the disparity in levels of funding, mostly, but not entirely, because of differing television deals. This leads to the rich becoming richer and more powerful on the football field.
There will be those who will argue it was ever thus. Real Madrid won the first five European Cups and no-one has ever confused them with being the paupers of the continent.
However, a glance at subsequent winners shows how the game in Europe has changed and how the balance of power has switched to major leagues. For example, Benfica won two European Cups in the sixties? Can anyone see that being replicated? Lawwell's Celtic also won in 1967 but his club would now consider progression to the knockout stages a triumph.
And how about the Dutch? Ajax and Feyenoord won four successive European Cups from 1970. This season the former dropped from group stages into the Europa League where they were beaten 6-1 by Salzburg and the latter were eliminated in the play-offs for the same competition. What price the home of total football supplying the winners of the Champions League in the near future?
Yet Benfica, Celtic, Ajax and Feyenoord all won the top competition before any German side. They say sport is cyclical but the air has gone out of the tyres of those who once were the leaders of the European game. All this, of course, can be brushed aside with a wringing of hands and an adoption of a philosophy that states that nothing stays the same and everyone will just have to become accustomed to the new reality.
However, the problem for the clubs is growing, even threatening. Limited access to television cash means a reduction in the quality of playing staff and a subsequent impact on supporters.
Celtic fans - and those of Benfica, Porto, Ajax, Feyenoord and a host of other one-time contenders - have now become attuned to limited European participation with sober ambitions. The concern for the boards of these clubs - and those in eastern Europe - is that there is no viable way forward under present restrictions on where they play their league football. This is the argument almost as old as European football itself. The dispossessed damn the tyranny of geography, the fortunate rub their hands and UEFA states that clubs must play in the same country as their ruling association.
The battle continues, however. It may be polite, even diplomatic. The ECA is always keen to emphasise its close, friendly relationship with UEFA but clubs throughout the continent and even within the big five leagues of Germany, France, Spain, Italy and England are beginning to move for change.
They want to escape the boundaries of their countries and play either in a neighbouring lucrative league - Benfica in La Liga, Ajax in the Bundesliga, Celtic in the Premier League - or set up a more formal European league.
Their argument is not just that it would be good for them - although it certainly would be - but that it would be good for European football in general.
This can be dismissed as self-serving but there is a further argument that is unanswerable. Portugal, the Netherlands, Eastern Europe and Scotland were once leading players in European club football but, perhaps more importantly, they are traditional football countries with a high rate per capita of attendances. Scotland, Belgium, the Netherlands and Denmark have a higher per capita rate of fans going to the games than in Spain, France, Germany or Italy.
This passion, though, is not limitless. Insistently, if delicately, UEFA are being apprised of this danger to the financial model, if not the very existence of clubs.
The battle over allowing clubs to play in non-national leagues has not been won. But no-one should doubt it is being fought.