You wouldn't expect the DUP or Boris Johnson to know about Seamus Darby. But Seamus is a legend in his own lifetime - and rightly so.

In September 1982 Kerry were heading towards a (then) historic five-in-a-row senior All-Ireland football title at a packed Croke Park, two points ahead of Offaly.

Offaly full back Liam Connor sensed the game was going away from the Leinster champions, so he ventures upfield.

He floats a high ball in towards the Kerry goal. Tommy Doyle, the tall full back, soars high, thinking he has all under control. Just as he is about to grasp the leather football into his hands, Tommy gets a gentle nudge into the small of the back.

Seamus Darby, 1982, scores Offaly's last minute goal (Sportsfile: Colman Doyle)

The 31-year-old substitute, Seamus Darby, grabs the ball and wastes no time in blasting it to the roof of the net, past Charlie Nelligan.

Brendan Lowry (father of golfer Shane, the one who made tricolours a fashion accessory on the 18th green at Royal Portrush) rushes over to congratulate his team mate. But Seamus has his eye on the prize.

"Get out quick," he says "it’s Kerry we are playing."

On Tuesday night, just as happened during Super Saturday, the DUP did a Seamus Darby on Boris Johnson.

"Boris is on his back, spread-eagled in the ditch, bruised, wondering if the DUP-inflicted back injuries are just seriously painful or terminal."

The British Prime Minister was almost out the gap. He could smell victory.

Unlike Theresa May, after more than three-and-half years of tortuous around the House prevarication, Boris had a deal almost in his grasp. He could smell it. He was in touching distance of it.

And then, as he soared high to collect the historic prize, he got the nudge in the back from the DUP.

The ball has gone and it would seem this particular game is over.

Hair raising...Johnson leaves 10 Downing Street for his second PMQs at the House of Commons

The numbers in the Boris vote on Tuesday were 322 to 308. The figures in his defeat on Saturday were 322 to 306.

If the 10 DUP members had sided with their former Very Best Friend rather than against him, they would have given him a six vote margin of victory on Saturday night and a four vote victory last night.

He and the minority Conservative government, kept in power by the DUP since the June 2017 general election, could have been heading for the Sunny Uplands, with the blessing of the EU 27, Leo Varadkar included.

But instead Boris is on his back, spread-eagled in the ditch, bruised, wondering if the DUP-inflicted back injuries are just seriously painful or terminal.

So much for Confidence and Supply. Confidence to supply the coup de grâce.

What would Brian Cowen say?

I wonder is Brian Cowen tracking the twists and turns of Brexit? Confirmation that he is slowly recovering from ill-health is lifting many hearts.

As Minister for Foreign Affairs and later as Taoiseach he was a player at many versions of long day’s journey into night political negotiations in Northern Ireland.

He had a colourful way of expressing his near exasperation when, one more time, the minutiae of orange/green tribal politics would suck in the resources of two sovereign governments and demand attention while idiosyncrasies and counter idiosyncrasies were indulged.

On the margins of one more inconclusive round table session in Hillsborough or the Stormont Estate, Brian Cowen would spot me, roll his eyes towards heaven and say "Cork County Council".

Brian Cowen was familiar with difficult negotiations in Northern Ireland

Our paths first crossed 43 years before. I was sharing a flat with Fermoy-born Maurice Gubbins, now the editor of the (Cork) Evening Echo, as we were first years in the Rathmines School of Journalism.

The bunch a year ahead of us was a more worldly, wiser crew. PJ Cunningham, later of the Sunday Independent, and Joe O'Brien, who became RTÉ's Agriculture Correspondent, were like our big brothers.

PJ gave us advice about how to survive in the packed Leinster Cricket Club and Mount Pleasant Discos. "Lie in and hold tight."

There was a wonderful movie at the time, featuring Paul Newman and Robert Redford about two grifters. It was called 'The Sting' and had a great Scott Joplin music score. We nicknamed PJ 'The Sting'.

PJ sometimes had a weekend visitor from his home place, Clara, Co Offaly. The guest was younger than us, even shyer and he was stone mad on football. Unusually, for a Gaelic player, he could kick with both feet, left and right. His name was Brian Cowen.

Back in Clara, his father Ber, was the local publican, butcher, undertaker and politician. PJ Cunningham once told us how the Cowen hearse would sometimes be commandeered to go to dances or greyhound meetings.

Brian Cowen’s availability for football ended prematurely at the age of 24. In 1984 his 51-year-old father died suddenly. The son contested the by-election to succeed his father. Circumstances decided that his focus should now be the game of politics. (Earlier this year, PJ Cunningham finally got round to assisting Seamus Darby with his autobiography, About That Goal).

The best of times, the worst of times

"The DUP had been consistently told by the prime minister who called the referendum, David Cameron, that in terms of the overall contest, he would win the day."

But what of the DUP and the fine margins involved in the game in which they are now centre stage?

23 June 2016, polling day in the Brexit Referendum, was a Thursday. That afternoon, in her role as Northern Ireland first minister, Arlene Foster officially opened an extension to a new printing company in east Belfast. The local DUP Assembly member, Sammy Douglas, was with her.

We chatted, in a small talk way, about Brexit. It was safe to assume that earlier that day Arlene had probably cast her vote in line with the party’s Leave stance.

Sammy was, and still is, a good friend of Martin McAleese. I have reason to believe Sammy was one of those Unionists open to Remainer arguments.

There was no sense at the time that the numbers were drifting to favour the Brexiteers. On the ground in Northern Ireland, the strongest vibes coming through were in favour of Remaining - the eventual outcome in Northern Ireland.

The DUP had been consistently told by the prime minister who called the referendum, David Cameron, that in terms of the overall contest, he would win the day.

The DUP's Nigel Dodds and Arlene Foster leaving Downing Street

But in different printing houses, completely unrelated to the enterprise visited by Arlene on voting day, the DUP had made what history may ultimately judge to be a highly significant intervention.

The DUP organisation was the vehicle used to fund a £400,000 last minute advertising campaign designed to influence a crucial swathe of the electorate as it prepared to vote. The wrap-around cover on The Metro freesheet newspaper urged voters to 'Take Back Control'.

It was distributed to hundreds of thousands of commuters up and down the neighbouring island but was never handed out in Northern Ireland.

The funds to finance the intervention were lodged in DUP coffers by a little-known organisation, The Constitutional Research Council.

The mechanism of transferring the funding to a party based across the Irish Sea (and then using it to fund a Great Britain campaign) meant no GB rules about spending limitations were breached.

Just as the DUP didn't expect the Brexit Referendum result, they certainly didn't anticipate the bounce the party would get from the snap election, called by Theresa May in June 2017.

Ten MPs, who at best had "visiting country cousins" status among the Tory high-flyers at Westminster, were suddenly catapulted to celebrity status. They were now in three (free) dinners a day territory if their busy schedules could accommodate it.

The DUP responded to the kingmaker's role with impressive zeal. It thwarted Theresa May in her original proposal to allow Northern Ireland only to remain in the EU’s Single Market and Customs Zone.

A humbled prime minister was then forced into her Plan B role - included the backstop and an arrangement to keep the UK close to EU customs union and single market standards for the foreseeable future.

While the DUP extracted impressive sums of largesse from Westminster for Northern Ireland, it kicked against Prime Minister May’s "softish" Plan B deal. Its 10 members and the policies articulated by party leader, Arlene Foster, had a significant role in her undoing.

The DUP then became critical if indirect players in the selection of her successor Boris Johnson.

Boris and the DUP - the breakdown

When Love Breaks Down,

The Things You Do,

To Stop The Truth

From Hurting You...

1980s band Prefab Sprout was responsible for the song, 'When Love Breaks Down'. Thirty years later, Northern Ireland’s Snow Patrol released a useful cover version. Some of the lyrics capture what has happened between Boris and the DUP.

He ditched them because his focus switched to getting a deal and to prepare for the inevitable, more complex down-the-road negotiations with the European Union.

They took their revenge, twice, because they felt slighted and that is a very uncomfortable status in a public space. Reality eventually intervened in the holiday romance.

Just as there are very few poor bookies, 10 MPs, presenting a minority position from Northern Ireland, could not indefinitely set the terms of engagement and decide the outcomes in UK and EU power politics.

Schadenfreude - taking pleasure in another's misfortune or "I told you so-ery" - is not the appropriate adult response in the situation.

A deeper understanding of each other, remembering those from North and South who died in World War I as well as remembering all the victims of our sad wars, was one of the cathartic, energising forces of recent years.

That’s what was happening, slowly, on the island - we were all beneficiaries - before Brexit intervened.

There is no good side to hearing of loyalist groups gathering in their communities in recent weeks to mull over the dispiriting signals coming from Westminster.

Those who use phrases like "surrender" and "betrayal" may not fully understand how their words might be a building block for unintended consequences in a place that has endured far too much sadness in the not too distant past.

Last Saturday night, most of the 10 DUP MPs who had made their significant intervention in Westminster travelled home together on the London Heathrow-Belfast flight.

Some of the Sinn Féin non-voters were on the same plane. I waited outside Belfast City Airport for the "voter MPs", conscious that some of the group had read my online piece, detailing how they had shafted prime minister No 2.

One of the first out of the main doors was Nigel Dodds' wife, Diane, the MEP who will be made redundant from her job as soon as the UK leaves the EU.

She has the ability to be as effective a force in Strasbourg as Mairead McGuinness or Marian Harkin (before she retired). But she will never fulfil her potential in that arena.

She was followed soon after by Sammy Wilson. He is always good for a fiery quote about Brexit because, as he acknowledges himself, he has a blind spot about the EU and the rules set out in its Treaty of Rome.

But every time I see him I remember him travelling down to the Catholic church outside Porterstown in Dublin to pay his respects to Brian Lenihan junior.

And then there was Jeffrey Donaldson, who never ceases to return a phonecall and never loses his temper when, for the umpteenth time, a passing stranger tells him he looks like Daniel O’Donnell.

Nigel Dodds stopped and obligingly did an interview. Sammy and Jeffrey stood beside him. They joked about the mildly ridiculous sight of a talking politician with silent colleagues alongside and agreed it an Irish phenomenon. We laughed about some invisible, Father Ted-style border down the Irish Sea.

The DUP and 'climate change'

"Once the election date is set, the first rule of politics will kick in - survival."

The DUP must now urgently deal with "climate change". They have gone from being high-rollers to a situation where they can’t buy a break.

Their role in twice shafting Boris and the Conservative party, Brexiteers included, has been noted. Everyone in the European Research Group, from Jacob Rees-Mogg down to Andrew Bridgen is giving them a wide berth.

Unionist politicians at Stormont failed in a last-ditch effort to block new legislation

The Westminster parliament where they once had such clout, has now cleared the way for the introduction of gay marriage and abortion provisions to Northern Ireland.

They failed in their efforts to use some mathematical three-card trickery - and they have form - to temporarily revive Stormont on Monday. One of their own, Robin Newton, in his role as Assembly Speaker, had the decisive Speaker John Bercow-style cameo role in dismissing the gamble.

The RHI report is cooked and must be on course for presentation, although the scheduling of an election may affect the publication date. It certainly won't help the perception of the DUP.

Some of the 10 MPs - in particular Emma Little-Pengelly in south Belfast - will be struggling when the Westminster contest gets under way.

It will be a bruising campaign. There is little logic in them demonising Boris or the Tories but Leo Varadkar and Simon Coveney will be seen as fair game and "the interfering southerners" may come in for dishonourable mention.

Once the election date is set, the first rule of politics will kick in - survival. While that battle is taking place there will be no space or no sense in seeking to have power-sharing at Stormont restored.

The DUP wouldn't thank one for the observation. But is a lesson of the whole Brexit saga that if you constantly shout wolf, there is a danger that a wolf will turn up some day?

In the meantime, the DUP have their party conference this weekend. For years they have been the dominant, going places voice of unionism and the largest Northern Ireland Assembly and Westminster force.

Good luck to the speech writers for this event. Last year Boris Johnson, the leader-in-waiting was the star turn.

Boris Johnson attended the DUP conference last year

He confused some of the attendants by talking about building a landbridge to Scotland. Many in the audience would know the price of a bag of cement and a lorry load of stones and they would struggle with the notion of building a connection to Scotland while Northern Ireland has a potholes issue. But, as Boris does, he gave the event oomph.

It was an indication of the DUP’s clout that the Chancellor, Philip Hammond, was also a guest even though the cracks were appearing in their relationship with his boss, Theresa May.

Who might they go for this year? Boris has a capacity for doing somersaults but even he might struggle to do an Incredible Hulk spin and arrive centre stage at the DUP gathering?

Nigel Farage is probably busy in his role as a member of the European Parliament and, as he recently confirmed, he prefers to drive rather than fly or take the train on that very long road to Strasbourg.

But how about the man who made history? Could he lift the gloom?

Send for Darby. Seamus Darby.