Having lost just once in six matches to Croatia, the Boys in Green led by talismanic Robbie Keane have an advantage over their Group opponents. Apart from the positive return of two crucial players Shay Given and John O'Shea, coach Giovanni Trapattoni men will take on Croatia on the back of a 14-game unbeaten run.
The Italian coach has suffered just two competitive defeats since taking over the Irish side back in 2008. Having crawled through the qualifying phase, Trapattoni's men are up against the likes of Spain and Italy, willing to prove a point in Europe's biggest stage.
Despite this vast improvement, Ireland managed only one win in three friendlies. The recent draw came against Hungary prior to the start of their Euro 2012 campaign.
Meanwhile, Croatia have been hit by injury to key players like striker Ivica Olic, who will miss a portion of the tournament with a thigh injury. Olic's replacement would be in-form striker Nikica Jelavic. Moreover, defender Dejan Lovren and midfielder Ivo Ilicevic have been ruled out Euro 2012 due to injury.
But coach Slaven Bilic will be relieved to have right-back Verdan Corluka, who was declared fit to play. Centre-back Josep Simunic will partner Gordon Schildenfeld while Ivan Strinic is likely to start on the left-hand side.
Play-maker Luka Modric, who has had impressive season in the English Premier League, can wriggle through opponents and open gaps in the defensive back-line. Modric along with captain Dario Srna, Ivan Rakitic and Danijel Pranjic will control the midfield.
Apart from Jelevic, Nikola Kalinic or Mario Mandzukic will form the attacking front line for Croatia.
Republic of Ireland: Given-O'Shea, Dunne, St Ledger, Ward-Duff, Whelan, Andrews, McGeady-Long, Keane.
Croatia: Pletikosa-Corluka, Schildenfeld, Simunic, Strinic-Srna, Modric, Rakitic, Pranjic-Kalinic, Jelavic.