Manager Michael O'Neill expressed pride after seeing his bold gamble pay dividends in Lyon as a much-changed Northern Ireland side kept their Euro 2016 hopes alive with a 2-0 victory over Ukraine.
A 1-0 defeat by Poland last Sunday had left Northern Ireland teetering on the brink of elimination but, four days later, O'Neill responded by changing five players in his starting line-up, dropping the likes of Kyle Lafferty, Paddy McNair and Chris Baird and reverting to a 4-5-1 formation.
Those that came in stepped up, though, and goals from Gareth McAuley and substitute Niall McGinn ensured a first victory at the European Championship finals, and a first at a major tournament in 34 years, meaning a last-16 berth could be sealed in Paris against world champions Germany next Tuesday.
"I'm just delighted for the players and the work they've put in," O'Neill said.
"They were down for longer than I wanted against Poland yet that reaction was fantastic. It showed me how much they were hurting. Individually they were disappointed with some of the performances in the team but when you get that reaction, then you can't ask for any more.
"As I said to the players, it was probably the proudest I have felt, certainly in the dugout and probably throughout my football career.
"As a manager you can be tactical, you can be organised and you can ask for different things, but when you get a performance like that, which is just pure commitment, pure heart, there's nothing more you can ask for."
The time spent on the Poland post-mortem had led to some radical tinkering for O'Neill, who knew his country's fate would rest on his roll of the dice.
"We did so much work leading into the first game, the work we did was of a really high quality, the players took it on board," he added.
"Whether it was a combination of Poland being very good or us being below par you do question yourself a little bit.
"It was probably the proudest I have felt, certainly in the dugout and probably throughout my football career." - Michael O'Neill
"I just felt having watched it back from the different camera angles we needed to get more running power into our team in the middle of the park and in the wide areas.
"We had always planned to play four at the back because of Ukraine's threat from the wide areas with (Andriy) Yarmolenko and (Yevhen) Konoplyanka, we'd be more suited to the 4-5-1 we played in qualifying for this game. The two boys at full back...how they dealt with the two wide players was magnificent.
"There was big decisions that had to be made, it's never easy changing half your team and it was difficult to leave lads out, it's not as if they didn't give me everything on Sunday. I had to make those decisions and thankfully they paid off."
Northern Ireland now take on world champions Germany next Tuesday, kick-off 5.0pm, in their final Group C game with qualification to the knock-out stages to play for.
