The Republic of Ireland's Euro 2012 campaign got off to the worst possible start in Posnan when the lost 3-1 against Croatia.

Two goals from Mario Mandzukic and one from Nikica Jelavic ensured there was no winning return after a decade in the international wilderness for Giovanni Trapattoni's side.

Croatia went ahead after just four minutes when Mandzukic steered a header past goalkeeper Shay Given after Ireland failed to clear Ivan Strinic's attempted cross.

Ireland looked to hit back immediately as Damien Duff and Keith Andrews both went close before Sean St Ledger turned in Aiden McGeady's free-kick to level the score.

Nevertheless, Croatia seized the initiative just before half-time when Jelavic pounced on Stephen Ward's sliced clearance to poke the ball over Given and into the roof of the net.

Croatia almost made it 3-1 before the break when Ivan Rakitic headed over from close range. Ireland went in after 45 minutes complaining about a possible offside for Jelavic's goal but they could have no complaints at the manner with which they relinquished the tie three minutes into the second half.

Mandzukic rose to meet a cross from the left and his header hit the post before finding the back of the net via an unfortunate deflection off the back of Given's head.

Croatia's third took the sting out of Ireland's challenge and in truth they never appeared capable of overcoming the quarter-finalists from four years ago.

Trapattoni's side will need to bounce back quickly if they are to have any chance of making the next round with defending champions Spain and Italy to come.