The 31-year-old LA Galaxy frontman struck twice in Friday night's 4-0 Euro 2012 play-off rout of Estonia in Tallinn, prompting club boss Bruce Arena to suggest he could head back to Los Angeles to prepare for Sunday's showdown with Houston Dynamo.
However, Keane was not about to pass up the opportunity to celebrate qualification for a major tournament finals for the first time on Irish soil against the battered and bruised Estonians at the Aviva Stadium Tuesday night.
The Ireland captain said: "They requested could I come back to LA, but obviously the manager and myself and everyone have said 'No', because it's still halfway.
"Even though it would be a tragedy if we didn't qualify now, the job is still not done yet. We have to be professional and do the job properly.
"They requested me to come back with the final on Sunday, but this could be one of the greatest moments in Irish history for me playing for my country, and to miss a special night - hopefully - like this tomorrow night, it wouldn't feel right."
Asked if Galaxy had been annoyed at the decision, Keane insisted they had understood.
He said: "No, no, because I am with the national team. It would be disrespectful to the players and everyone associated thinking that the job is 100 per cent done.
"We know in football anything can happen. They requested it and they were happy with what the manager and the Association said, so believe me, it's no problem."
It is 10 years since Ireland made it to a finals tournament, the 2002 World Cup in the Far East, and on that occasion, they also took the play-off route.
But skipper Roy Keane, who had headed off on international duty nursing an ankle injury, was not present as their trip to the Far East was confirmed in Tehran having, to the surprise of many, returned to Manchester United following a 2-0 home win over Iran in the first leg.
The current skipper said: "I don't want to get into what happened in the past, I can only speak for myself and what Ireland means to me, and you all know I turn up for every game.
"If I have got a slight injury, I still come in and try my best to play the game, that's just the way I have been brought up, that's the kind of player I am.
"My country means everything to me. I would never not turn up. I have never done that in the past, and I can proudly say that.
"Roy was a top, top player and whatever happened to Roy in the past, that's something you would have to ask him.
"I can only speak on behalf of me and for me, this is probably one of the proudest moments my footballing career, to lead this team to where we are now and to achieve what we have achieved."
Keane admitted he had never before had the luxury of heading into the second leg of any tie with such a substantial lead, but has experience of how a seemingly impregnable advantage can be over-turned after finding himself on the wrong-end of a remarkable FA Cup fightback by Manchester City as a Tottenham player.
In February 2004 at White Hart Lane, Spurs were leading City's 10 men 3-0 at half-time and coasting, but contrived to lose 4-3.
Keane said: "I was actually playing against Richard [Dunne] - we even speak about it now - and we were chatting through the game and Richard was saying, 'Imagine if we came back and beat you', and I said, 'No chance, it's not going to happen'.
"Then every five minutes, they seemed to get a goal and we ended up losing the game 4-3.
"That's what I am saying - in football, anything can happen, so we have to be professional and do the job properly."
Professionalism was a theme which ran through Ireland's pre-match press conference with manager Giovanni Trapattoni citing Keane's desperation to see the job through as evidence.
He said: "I was in Germany and Portugal and Italy and I have in my life worked with 2,000 players and I have been lucky with those players because they had this commitment and this seriousness and this professionalism.
"Two years ago, it was impossible for me to understand that, when we said the players could go out and that they had to be back at 10pm, some came back at 1am.
"It's a professional mentality and now 99 per cent have got the message, but one per cent still haven't."