With the top spot in Group C up for grabs in Poznan on Sunday night, the Republic of Ireland could gave up three tough goals to Croatia in their 3-1 loss.
The Croatian onslaught started early when Mario Mandzukic put a header past Irish keeper Shay Given in the third minute.
Things were looking up for The Boys in Green for most of the first half, especially after Sean St. Ledger headed home an Aiden McGeady cross in the 19th minute to tie the game.
But that would be one of the few positives that Giovanni Trapattoni's team took out of the rainy night in Poznan, Poland.
Right before halftime, a scuffed cross by defender Stephen Ward ended up at the feet of Croatian forward Nikica Jelavic, who put the ball past Given to retake the lead for Croatia.
Moments after the goal was scored, most of the Irish players were screaming at referee Bjorn Kuipers, but the complaints were to no avail as Jelavic was put onside by the mishit clearance by Ward.
Going into halftime, Trapattoni's men were down a goal and were looking to play better in the second half but those dreams were crushed just three minutes into the second half.
Mandzukic scored his second goal of the game in the 48th minute with shot that hit of the post then bounced off the body of Given and into the net.
Down two goals, Trapattoni brought on three forwards, Jon Walters, Simon Cox and Shane Long, to try and get something going but that was not successful either.
Ireland thought they had a penalty in the 62nd minute when Robbie Keane was brought down by Gordon Schildenfeld in the box but Kuipers has nothing of it and kept play going.
The closest that The Boys in Green came to a scoring chances came late in the match when midfielder Keith Andrews put two shots on goal, one went over the bar and the other wide right.
Now, after one game in Poland, the Irish sit at the bottom of the group with zero points ahead of their match with defending Euro and World Cup champions Spain on Thursday in Gdansk.