Los Angeles Galaxy striker Robbie Keane has highlighted continuity as the reason for the Republic of Ireland's success.

Since taking over as manager four years ago, Giovanni Trapattoni has predominantly selected the same group of players for international duty. Keane admits that this has helped the players to become use to each other and contribute to bettering the side.

"That's been the case for the last few years, we have had really the same squad for the last few years now," said Keane.

"In the last campaign, it was a very, very similar squad and the players with every game get better and better and they get more comfortable playing international football.

"The starting XI has been kind of the same for a long time now, so the players are very, very comfortable with each other, and the players who are on the bench or who come on know exactly what role they have to play when they come on to the pitch.

"For a player, it's very, very important to know that."

Ireland qualified for Euro 2012 after beating Estonia in a two-legged playoff.