The 31-year-old will lead the Republic of Ireland into play-off battle with Estonia in Tallinn tomorrow night having spent almost a decade reflecting on his trip to the World Cup finals and the fact that qualification has eluded his country ever since.

That could all change over the next few days as the Republic and Estonia go toe-to-toe with a trip to Poland and the Ukraine next summer up for grabs, and it is an opportunity Keane is not prepared to let slip.

Asked how those barren summers have been, he said: "A pain in the a***, to be honest with you. It's even hard to watch, especially the last World Cup, when we were that close.

"This is what you play football for, this is why we are here. Playing the friendly games is great and playing for your country is the best experience you can have.

"But this is why you play football, to play in these big competitions, and we can't let it slip away."

Keane, who has shaken off an adductor muscle injury ahead of schedule to make himself available, is one of the few members of the current squad to have played on the big stage, making his name around the world with his performances in the Far East in 2002.

But the heartache of Ireland's controversial World Cup play-off defeat by France two years ago has simply increased his hunger.

The Los Angeles Galaxy frontman said: "It would mean everything. I have been fortunate to play in a World Cup, which was one of the best experiences of my life, but I haven't played in a European Championships yet.

"Every time you watch one of the TV, you are just desperate to be there. We haven't qualified for 20-odd years, so it would mean a hell of a lot to me and the whole country.

"This is a great opportunity for everyone. For players like myself, Shay Given and Richard Dunne, this could be our last opportunity, so we have to grab this with both hands.

"We have worked really, really hard to get where we are, so we can't let this just slip away. I know for a fact every player is desperate for this.

"Listen, this could change the whole country, give the whole country a massive, massive boost, which it hasn't had for a while."

Ireland's most recent play-off adventures have been played out in front of packed houses in Teheran and Paris, while tomorrow night's first leg will unfold in front of a capacity 10,000-strong crowd at the neat A Le Coq Arena.

However, Keane insists the surroundings make little difference to the task at hand.

He said: "You have to treat every game the same. You have to respect your opponents - they are here for a reason.

"They have obviously done well and they are in the exact same situation as us.

"Of course, when you are playing teams like France who are the favourites and have got these world star players, Estonia don't have that, but do we?"

If Keane is the Republic's talisman - his haul of 51 international goals is far and away a national record - Estonia could have one of theirs back with midfielder Joel Lindpere having ended his self-imposed exile from the national team.

Keane had a chance to run the rule over the New York Red Bulls star just weeks ago when the Galaxy beat them over two legs in the MLS Western Conference semi-final.

He said: "He's a great player for Red Bulls and I think he has come out of retirement to play these games, so he is obviously very, very important to the Estonian people and the manager.

"He's a very, very good player. He played well in the two games and I have seen him on numerous occasions for the Red Bulls, so he is definitely a player we will have to watch."

Lindpere is a team-mate of Thierry Henry, whose handball led to the discomfort in Keane's backside two summers ago, but asked if the pair had discussed the forthcoming play-off games when they met up, the Irishman said with a smile: "Yeah, yeah, we had about an hour's chat about it before the game.

"What do you think? Of course we didn't. I was fully focussed on playing for the Galaxy and him playing for Red Bulls.

"We just said hello and shook hands, and that was it, really."