QUESTION: what is the biggest 'derby' taking place on these disunited islands this weekend?
Is it Wales v England in the Six Nations Egg Chasing Championship tonight? Or Tottenham 'Born In North London' Hotspur versus 'Woolwich' Arsenal, first thing tomorrow morning? Perhaps you're a Toffee craving light relief from mid-table mediocrity by dint of conquering Merseyside tomorrow evening?
Or maybe just one result matters to you - tomorrow's Navan clash of Mick O'Dowd's (pictured) reeling Royals, managed by Mick O'Dowd (pictured) and labouring Lilywhites.
In the strictest meaning of 'local derby', Meath/Kildare certainly qualifies although it still doesn't make it into the GAA's Deadly Enemy Premier League. Cork/Kerry, Dublin/Meath, Tyrone/Armagh, Kilkenny/Tipp, Clare/The World are all further up the festering hatred table.
Here's a thought: how about Dublin v Donegal at Croke Park tonight?
We can already hear the pedantic outrage: how can two counties separated by well over one hundred miles, even at their nearest points, be deemed derby rivals?
But that's the thing about derbies in this era of globalisation: the emphasis is now much less on the word 'local' and far more on 'rivals'. Geography is only one (important but not entirely crucial) element of our poisoned relationship.
When it comes to Gaelic football, Dublin/Donegal doesn't constitute a derby - yet - but it's getting there, by dint of that notorious All-Ireland semi-final in 2011, the Ballybofey 'Bitegate' controversy of 2013 and the shock-horror result of last August.
Rivalries evolve - some almost disappear, others sprout from nowhere - and success is usually a central component. That's why Cork/Meath was so toxic in the late 1980s and is now almost benign.
As the Ulster football championship vividly (and sometimes violently) underlines on a perennial basis, the province is a raging torrent of truculence. Yet even within this unique ecosystem, some traditional rivalries fade in relevance (Down/Armagh) and are superseded by others - such as Tyrone/Armagh, who bring out the crowds and the bile in equal measure, even for the McKenna Cup.
The funny thing about GAA rivalries is how some of them are seen to be based on grudging respect, bordering almost on friendship - Mayo/Galway springs to mind - whereas Mayo fans would appear to be far less appreciative of their Rossie neighbours. And vice versa.
No matter what the code, managers play a pivotal role in fomenting these rivalries. Iconic players too. Man United v Arsenal is not a derby in strict geographic terms, but when Alex Ferguson and Arsene Wenger were in their pomp, Roy Keane and Patrick Vieira their on-field enforcers, and their clubs monopolising the top of the Premier League, even pizza slices could be utilised as weapons and it was every bit as bitter as Arsenal/Spurs or United/City.
By the same token, Chelsea v Liverpool has mutated into the rowdy stamp-fest it is today largely through the inflammatory jousting of Jose Mourinho and Rafa Benitez, starting over a decade ago. Rafa is long gone but the spitefulness lives on.
And the biggest rivalry of them all? Forget Man U v Liverpool, much as they loathe each other. Nor the class divide that is (or was) Leinster's D4 rugger-buggers against Munster's broad church - these same guys would then die for each other in the Irish jersey a week later. The politico-religious nonsense of Celtic v Rangers? Eh, let's keep it relevant.
Which can mean only one thing: Ireland v Australia in the ... International Rules!