It was completely the opposite to the way the nations had voted two days ago. Northern Ireland had opted to stay in the European Union in the Brexit vote, while Wales had proportionally chosen to leave. But on the football field, it is Wales that remain at the Euros as Gareth Bale inspired a hard-fought win in Paris.
It was anything but easy, though. Nothern Ireland played defensively but were a match for their rivals for much of the 90 minutes. In fact, Michael O'Neill's men restricted Wales to very few chances and also created the pick of the opportunities themselves in the first half - when Stuart Dallas saw a fierce shot saved at the near post and Jamie Ward tested Wayne Hennessey from long range.
This was never going to be a classic. Described by O'Neill yesterday as "an old-fashioned British cup tie", it was very much like that. Northern Ireland defend deeply, often with five or even six players, while Wales play their best football on the break. Hardly the ingredients for a memorable encounter and so it proved.
But Northern Ireland deserve immense credit for reaching the last 16. A mix of mainly lower-end Premier League and Championship players, they punched above their weight in this tournament and for a while looked like taking Wales all the way to extra time and penalties.
But Bale intervened. This was hardly his finest performance and he was well marked in a physical battle at the Parc des Princes, but the Real Madrid winger still provided the moment of magic needed to send his side though to the last eight of a major competition for the first time since 1958 as his dangerous cross from the left was deflected in by Northern Ireland defender Gareth McAuley with 15 minutes left.
So 58 years after they lost 1-0 to Pele's Brazil in 1958, Wales are back in the big time in an elite competition. And in the easier half of the draw, the Welsh can be considered as outsiders to go all the way to the final in Paris on July 10.
Next up will be the winner of the game between Belgium and Hungary and with Bale in such decisive form, there is a real possibility that the Welsh could have a big say in the final stages of this competition.
Having hit goals against Slovakia, England and Russia in the group stages, Bale made this one to end up as Man of the Match once again and he celebrated with his young daughter on the pitch afterwards, when she drew huge applause by scoring a goal into the empty net at the Wales end.
So in the end it's Wales in and Norhern Ireland out. A couple of days after Britain voted to leave the European Union, the Welsh remain at the Euros - and they won't want to return home any time soon.
With Bale in their team, they may not have to.