After Ireland's 3-1 win in Moldova last year, when Shane Duffy was very visibly responsible for the concession of the Moldovan goal, his partnership with Ciaran Clark was adjudged an accident waiting to happen.
The high priests of the punditocracy pleaded for change ahead of the intimidating trip to Vienna, insisting that O'Neill would regret it if he persisted with the pairing.
After the 1-0 win over Austria, there was, needless to say, no more of this talk. Everyone decided more or less in an instant that this was now to be our central defensive partnership for the foreseeable.
Like Darren Randolph and latterly David Meyler, Duffy went from being an object of apprehension among his own supporters to a seemingly indispensable figure in rapid quick time.
Duffy made his international debut in a friendly against Costa Rica in Philadelphia in June 2014, a time of high apathy in the history of the Irish football team. It didn't help that the games kicked off well after midnight over here.
It wasn't until two years later that he was elevated to the front rank of Irish defenders. With no competitive minutes under his belt, he only sneaked onto the plane for Euro 2016.
Not included for the first two games, Duffy was torpedoed into the starting line-up after Ireland's desperately limp effort against Belgium, an apparent beneficiary of Martin O'Neill's alleged selection criteria when his back is to the wall, namely, to stride into the dressing room and ask 'who's big and has loads of tattoos?'
After that famous win, then stand-in captain Seamus Coleman reminded reporters of what Duffy had been through and how far he'd come.
"Let’s not forget that Shane Duffy was nearly dead six years ago," Coleman told his audience. "For him to be back on the pitch is massive but to put in a performance like he did was incredible. And it was his first competitive international."
A FREAK INJURY WE MAY NEVER SEE AGAIN
It was May 2010 when the incident happened. Duffy was an 18-year old centre-half making his way in the reserves at Everton.
A former Northern Ireland U21 and a one-time unused substitute for the senior team, Duffy had only recently taken the leap and switched his allegiance to the Republic of Ireland.
Liam Brady was a central figure in affecting this switch, ascertaining that Duffy's heart was with the Republic and making contact with his parents and coaches at Everton.
"It came to my attention he could play for us and was willing to play for us. I was in touch with Everton, the player and his parents. I spoke to David Moyes about him and he thought he had a future," Brady told the Brighton Argus last year.
Under the watchful eye of Giovanni Trapattoni, Duffy played for the Republic of Ireland development side against the Ireland amateur side.
During the match a corner came in and Duffy collided with the goalkeeper Adrian Walsh, who accidentally caught the centre-half with his knees.
"A corner was coming in and the goalkeeper came out with his two knees. It was a freak accident, he actually nipped the artery going into his liver," remembered Duffy's father Brian who attended the game. (Irish Independent).
It struck observers initially as a painful but nonetheless fairly routine collision. However, the Irish medics were quick to spot that something very grave had occurred.
It transpired that Duffy ruptured the blood supply to his liver and had to be rushed to the Mater Hospital. Brian Duffy was in the ambulance and remarked later that his son had "turned grey" during the journey.
Mater surgeon Gerry McEntee (two-time All-Ireland winner with Meath) left a dinner early to return to the hospital to perform the emergency surgery. Brian Duffy, sitting in the hospital waiting room, was informed midway through the surgery by the Irish team doctor that "we could lose him here."
Ireland team surgeon Prof. John O'Byrne, who made the call that Duffy needed to be brought to hospital, left people in no doubt as to the gravity of the incident.
'Shane collided with a player in a way that you would see thousands of times in football matches. It was a freak injury that in another 100 years of medicine, we may never see again.
'Shane sustained a laceration to his liver and was rushed to the Mater hospital for emergency surgery.
"Gerry McEntee and the intensive care staff in the Mater must be credited for their expertise and fast response which in no uncertain terms saved Shane's life."
Duffy was back on the pitch less than three months after the accident.
THE LOAN YEARS
Duffy's career stalled over the subsequent years as he struggled to make the anticipated step-up to the senior ranks at Everton, eventually making only a smattering of first-team appearances in between loan spells.
These loans deals were typically month-long arrangements which were often extended.
He had spells at Burnley, Scunthorpe and Yoevil Toan, effectively playing a full season with the latter in 2013-14.
His loan days were over when he left Everton for Blackburn Rovers in the autumn of '14, a few months after his international debut.
Duffy enjoyed a couple of positive seasons at Ewood Park, establishing himself as the first choice centre-half.
However, his grimly comic final weeks in a Blackburn shirt seemed to sour all that went before and unfortunately provided the most lurid memory of his time at the club.
In a game away to Cardiff City in August 2016 - two months after his sterling display in Lille - Duffy scored two own goals and managed to get himself sent off in a game that Blackburn lost 2-1.
He received his second yellow in injury time for kicking the ball away and was treated to a standing ovation by the rival support. Three days earlier, he scored an OG against Wigan.
Needless to say, social media meme-makers worked over time and Duffy trended in certain locations.
Duffy was soon on the move - not because Blackburn were itching to flog him - but because Brighton shelled out £4 million.
Inevitably, his first goal for his new club came against the one he'd just left (it's an iron law of the universe that this must happen as often as possible).
Duffy shipped abuse, both in the stands and later on social media from Blackburn fans, and thus wasn't minded to bother with the solemn refusal to celebrate routine.
"It’s football, I’ve got no hard feelings. They (the Rovers fans) were giving me some, I gave it back. I enjoyed it," he told the Lancashire Telegraph.
It wasn't only his ex-clubs that were coming for him on social media. He would annoy a politicised strand of his new club's support for his tweeted tribute on the death of his fellow Derry man Martin McGuinness back in March.
More tragic news this morning, RIP Martin Mc Guinness a true hero for many off us 🍀 god bless your family and close ones #ireland
— Shane Duffy (@shaneduffy) March 21, 2017
But his performances remained steady and he was soon to become a Premier League footballer again.
Duffy was always present at centre-half in a side that conceded the joint fewest number of goals in the League alongside the other promoted team Newcastle United.
In August, he signed a four year deal which will keep him at Brighton until 2021.
Man of the Match in Cardiff
Monday night in Cardiff almost certainly represents the high point of Duffy's career so far. The internet's army of yapping statisticians tell us that Duffy managed 19 clearances last night and many readers are surprised to learn it was that low.
According to Ken Early on the Second Captains podcast, one of his (kicked) clearances went very close to actually hitting the roof of the stand, a rare feat.
Wales had been in sprightly mood in the opening 20 minutes, jauntily shifting passes from side to side, largely in the middle third of the pitch. However, that vim and verve slowly disappeared from their game as Ireland gained a toehold. The injury to Joe Allen removed a vital linkman and caused their midfield to malfunction.
At half-time, there was a growing sense that they had fired whatever bullets they had in the cartridge and it was now perfectly teed up for a Martin O'Neill smash and grab.
It was after the goal that Duffy truly came into his own.
Wales's panicked attempts at an aerial bombardment in the final half hour played right into Duffy's hands and his forehead connected with ball time and again.
Whether Duffy's performance last night will occupy the same place in Irish football folklore as Richard Dunne's in Moscow 2011 is tough to say. The rest of the Irish team weren't so helpless in Cardiff last night as they were in Russia six years ago.
But while Irish fans of the more purist stripe may yearn for Wes and his ilk, and indeed have a pain in their face talking about him, there is also a deep and stirring appreciation for the redoubtable and physically imposing centre-half.
Duffy's performance last night surely belongs in the battling Irish centre-half hall of fame. It stands as a towering display in one of the most important and satisfying Irish victories in the modern era.
