Croatia are capable of surprising at Euro 2012, but face what is a crucial opening clash against the Republic of Ireland.
Slaven Bilic s side are not favoured to progress from a Group C which includes reigning world and European champions Spain, Italy and Ireland.
But their chances of doing so would be dealt a huge blow if they suffer defeat against Giovanni Trapattoni s side on Sunday.
Former West Ham and Everton defender Bilic will take over at Lokomotiv Moscow after the European Championships, and will be eager to advance to at least the quarter-finals.
The 43-year-old has a solid squad at his disposal, led by Tottenham playmaker Luka Modric and Everton forward Nikica Jelavic.
With Darijo Srna likely to start on the right of midfield, Niko Kranjcar will be competing with Ivan Rakitic and Ivan Perisic for the other starting spot.
Jelavic, who earns his spot after the injured Ivica Olic s withdrawal from the squad, and Mario Mandzukic are up front, but the problems Bilic is likely to face will be in defence.
While Bayer Leverkusen defender Vedran Corluka is certain to start, Bilic s other options are less obvious after Lyon s Dejan Lovren withdrew with an Achilles injury.
Modric will be the key against an Irish side who will fancy their chances of making a good start to the tournament with a win at Municipal Stadium in Poznan.
Ireland are expected to be tough to break down but could struggle for goals, with their reliance on captain and Los Angeles Galaxy forward Robbie Keane.
In a massive boost for Trapattoni, Aston Villa goalkeeper Shay Given was declared fit to play after a calf injury.
His club team-mate Richard Dunne will play his role in the centre of a defence which gave up just eight goals in 12 qualifiers.
Damien Duff, 33, has lost a yard of pace but is still crucial out wide for Ireland.
Both teams have plenty to lose ahead of tougher encounters, and Bilic will be desperate for his side to avoid an upset loss.
