Michael O’Neill had spent the build-up to Northern Ireland’s Nations League outing against Ukraine playing down memories of the famous win at Euro 2016.

His focus was firmly on what was to come.

If a stunning 3-0 victory in Slovakia was anything to go by, it’s going to be a pretty exciting future indeed.

His starting team had an average age of just 22, which was the youngest on record for Northern Ireland since World War Two.

Ciaron Brown, the only player over the age of 25 to start the game in Trnava, was in the right place to open the scoring in the ninth minute from Ruairi McConville’s knock down.

O’Neill handed a first start to 19-year-old Kieran Morrison, and his superb cross led to Isaac Price doubling the lead before Brown’s header evaded goalkeeper Dmytro Riznyk in bizarre circumstances with 30 minutes to go to round out the win.

While the win may not be quite as famous as the Kings of Lyon victory 10 years ago, it was extremely impressive.

To put the victory into context, never mind the manner of the performance, only Sweden and France had beaten Ukraine in the past 12 months.

Northern Ireland can now be added to that list.

Brown’s two goals were just reward for a player who has been quietly impressive for far longer than this campaign, and he was part of a back-five which stood out in what was a third consecutive clean sheet.

Brodie Spencer and Terry Devlin were drafted in at the full-back positions and both impressed, but Brown’s centre back partners McConville and Tom Atcheson really shone.

Norwich City defender McConville, 21, commanded his area and, as well as his assist for Brown, he also left the ball to trickle over the line when he could have touched home for the third goal.

Atcheson, himself only 20 and playing for Blackburn Rovers, made his Northern Ireland debut in Wales in March but showed composure beyond his years, and O’Neill said both players were “terrific”.

“They have no ceiling, to be honest,” O’Neill told BBC Sport NI.

“They are both playing in the Championship at the minute but they are ready to go to the next level.

“They will make mistakes at times and we’ve put a lot on them in terms of the physicality. The two of them were brilliant.”

O’Neill was also delighted for Brown, 28, who said he had “really grown” into a senior role in the absence of injured Sunderland defender Dan Ballard.

“Three 90 minutes at this level is tough,” O’Neill said about the Oxford United man.

“He plays his club football in League One and he’s a better player than that.

“He brings a lot to the team. He was our most senior player tonight and he has really grown into that.”

‘Everything fell into place’

When asked what was the most pleasing aspect of a positive night, O’Neill said it was the “overall performance”.

“We played a really good team tonight and we had to be really well set up,” he said.

“The team was really well prepared and the staff done an amazing job, from the analysis to the set pieces and right through everything.

“Everything fell into place a little bit, we scored early from a set piece and the second goal was brilliant.

“Another clean sheet and there were some really good performances right through the squad.”

With four goals scored and none conceded, O’Neill’s side are in great shape at the halfway point of the campaign.

They are three points clear of Hungary and Ukraine at the top of League B2, and host a Georgia side who have one solitary point to date back at Windsor Park on Monday night.

If they can end the quadruple-header unbeaten they will head into November’s final two matches on a high, and the wider implications are significant.

Topping the group would seal promotion to League A for the first time, and mean Northern Ireland will be in a five-team group for Euro 2028 qualification, with a potential fall back of a play-off should the campaign go awry.

Northern Ireland had not won an away Nations League match before Shea Charles’ 99th-minute winner in Georgia, and it is their biggest away win in five years.

Stephen Craigan on co-commentary in Slovakia described it as potentially “a seismic night” for a young group, which was missing Ballard, the influential Ethan Galbraith and Liverpool defender Conor Bradley, while Justin Devenny started on the bench.

The real implications of the win may only become clear further down the line, but for now all focus will be on the recovery ahead of the final game of the window on Monday.

“There is a big togetherness in a young group,” said Price, who scored his first international goal in just over a year.

“We’re loving it and we love coming away. It’s about building momentum and we’re doing that.”