There is a terrible beauty about Martin O'Neill's Ireland team. Though frequently terrible to watch, they have proved capable of pulling off beautiful results.
Monday's 1-0 victory in Cardiff "put a sword through the heart of the Welsh dragon," in the choice words of RTE commentator George Hamilton, and took Ireland into the World Cup playoffs. As Wales fans trudged tearfully away into the night, O'Neill and assistant Roy Keane took a leisurely, cheerful walk onto the Cardiff City Stadium pitch, the stadium by that point empty of all but a few stragglers asking "Keano" to give them a wave. With an uncharacteristic flourish, Keane granted that wish.
Two of the game's toughest customers were entitled to be enjoying the moment. Their team had beaten higher-ranked Wales, last year's Euros semifinalists, in much the same way they had downed Germany, in qualifying for Euro 2016, and Italy in Lille to reach the last 16 of the tournament itself. Whichever of Switzerland, Italy, Croatia and Denmark they're pitted against in Tuesday's playoff draw must expect two nights of attrition and to feel the bruises of facing Ireland, sore necks from tracking long balls punted into the air by a team that drags matches into quicksand.
Ireland have kept seven clean sheets in nine competitive matches. Each of those famous victories came by the same 1-0 scoreline, a winning goal snatched after long periods of entrenchment in the defensive third of the pitch. James McClean's strike on Monday came against the run of play, even if Wales had lost much of their momentum after Joe Allen was replaced after suffering a concussion caused by being sandwiched between Ireland captain David Meyler and McClean.
By the time McClean rattled in Jeff Hendrick's cross in the 57th minute, Wales were already embracing desperation. The wall of muscle O'Neill had placed across his defensive line and in midfield would prove impossible to breach.
"Once we started knocking it long, the Republic back four enjoyed that," admitted Wales manager Chris Coleman.
Where Scotland counterpart Gordon Strachan bemoans his country's genetics, O'Neill instead uses Irish football's characteristics to forge strategies built on a baseline of defending in depth to frustrate the opposition. His team has direct lineage in style to the football Ireland played when reaching the knockout rounds of the 1990 and 1994 World Cup finals, but he cannot call on anything like the same level of talent that Jack Charlton once had at his disposal.
There is no Keane in midfield or Paul McGrath, the master centre-back. Ireland's version of a star these days is McClean, a substitute winger for West Brom who offers just as much brawn as Ciaran Clark and Shane Duffy in central defence. McClean embodies a collective effort where pride and endeavour override the individual.
"We put our heads in places where players from other teams might not," said midfielder Harry After afterwards. After all, O'Neill and Keane demand a special degree of commitment.
"I've never doubted the character of the players," said O'Neill. "That's instilled in them. Their courage is never in doubt."
O'Neill is Ireland's eccentric autocrat, whose absent-minded public persona does not hide the hardness of his character. He and Keane are sometimes described as a partnership of bad cop and even badder cop but there is no consensus over which one is which. When the pair were appointed together in November 2013, Keane dismissed the idea that he might be O'Neill's enforcer with a sharp quip. "You don'r know Martin as well as you think you do," he said. "He makes me look like Mother Teresa."
In Cardiff, as O'Neill considered potential playoff opponents, he gave away a small something of his mindset. "Do we fear teams in it?" he said. "Absolutely. Every single one of them. Then we go out and beat them."
Fear of opponents is a trait that serves as both a positive and a negative. When their team huff and puff through matches with Moldova and Georgia, fans are entitled to be annoyed by a lack of adventure but in the biggest and most important games, it has proved a successful attitude. Only against France in Lyon at Euro 2016 did it fail, after the hosts had been given an almighty scare following Robbie Brady's early penalty.
Like the Welsh, Germans and Italy, France were being driven to distraction by Ireland's commitment. Previously dragged down to their opponent's level, it took two goals from Antoine Griezmann and a red card for Duffy to rescue the tournament hosts. O'Neill's approach is hardly novel, and in international football has brought great success to the likes of Otto Rehhagel's Greece in winning Euro 2004 and for Fernando Santos' Portugal in last year's Euros.
Ireland's ambitions are not so lofty, but their dogged victory in Cardiff suggested that they might yet spoil their way to the World Cup.
John Brewin is a staff writer for ESPN FC. Follow him on Twitter @JohnBrewinESPN.