The Republic of Ireland midfielder came off the bench to fire his side to a narrow Euro 2012 qualifier victory over Armenia in Yerevan on Friday night with his first senior goal for his country on his fourth appearance.
It has taken the 27-year-old Birmingham player, who is widely recognised as one of the richest talents to emerge from the League of Ireland in recent years, some time to win recognition on the big stage.
Indeed, a year ago, Ireland boss Giovanni Trapattoni, whose continuing struggles to pronounce Fahey's name correctly remain a source of amusement within the camp, knew him only by reputation.
But the 71-year-old had enough faith in him to introduce him for the final 22 minutes of a game which was in danger of going against the Republic in Armenia, and his trust was rewarded in style.
That came as a confidence boost for a man who has not had as much football as he would have liked for his club so far this season, and he is hoping his exploits on the international front can fuel his attempts to take the next step in the Barclays Premier League.
Fahey said: "It gives me great confidence. It's good to think that I am in his [Trapattoni's] thoughts anyway.
"There are other players he could have put on in front of me, so when I got the shout, I was delighted to get on.
"With the internationals, there are more games, you are involved more and your name is out there more, more people notice you.
"But this season, I will be looking to improve and try to get the best out of myself because I don't think I have shown the best of me yet."
Fahey's career has taken a circuitous route from a failed first spell in England, where it did not happen for him at either Arsenal or Aston Villa, through a revival back in Ireland with St Patrick's Athletic which ultimately won him his move to St Andrew's in January last year.
The club gave him compassionate leave in September last year when his father Declan died of cancer.
But older and more settled with compatriots Lee Carsley, Stephen Carr and Jay O'Shea having helped to ease him into life in the midlands, he is now ready to make the impact his ability suggests he can.
He did just that on Friday evening when, in energy-sapping heat in front of a hostile crowd, he did exactly what was asked of him and more.
The focus has now been shifted to Tuesday evening's Group B clash with minnows Andorra in Dublin, although Fahey, like the rest of his team-mates, will have to wait to see if his efforts at the Yerevan Republican Stadium were enough to earn him a first competitive start for his country.
Ostensibly a wide player, he insists he can play anywhere across the midfield, although he admits he does not know whether Trapattoni shares that view.
He said: "I can play anywhere. I don't know if the manager thinks I can play anywhere, I am not too sure - you would have to as him.
"But I can play anywhere across the middle, so it's a good thing to have.
"I know there are a couple of players out, but since I have come in, I have done well in training, so have as good a chance as anyone of playing. I would like to think so, anyway."
Trapattoni is not a man who makes changes for change's sake, and while Tuesday's game is likely to be less taxing than Friday's, he will not want to risk any slip-ups.
Keeper Shay Given sat out the latter part of training in Malahide this morning, but only to give the 34-year-old a rest, while defenders Paul McShane and Darren O'Dea were able to take part after recovering from injuries.
But asked if there would be changes, assistant boss Marco Tardelli was coy.
He said: "I don't know. The boss will decide. The team played very well against Armenia, but everything is possible because also the other players are very fit."