Mario Mandzukic scored a goal in each half as Croatia moved to the top of Group C at Euro 2012 following a 3-1 defeat of Ireland at the Municipal Stadium.
The two favorites in the group, Italy and Spain, played to a 1-1 draw earlier in the day, giving both Croatia and Ireland the chance to take the top spot with a win.
And Mandzukic made sure to give his side a quick start, scoring inside of three minutes.
Ireland responded with a goal from Sean St. Ledger in the 19th minute to equalize, but Nikica Jelavic restored Croatia's lead shortly before halftime, with Mandzukic adding another early in the second half.
The Irish rode a strong defensive record in qualifying to reach Euro 2012, but it took less than three minutes for the their defense to be breached.
Darijo Srna got to the end line on the right and had his crossing attempt deflected to Mandzukic, who was positioned near the penalty spot and who nodded the ball toward the bottom corner of the net, where it slipped past a diving Shay Given.
The Ireland goalkeeper appeared to react late to the header, but his side was pulled level in the 19th minute when a free kick from Aiden McGeady was played to the back post for St. Ledger to head home from inside the six-yard box.
Given did much better when he parried a powerful shot from Ivan Perisic a few minutes later, but a bit of misfortune just before halftime saw Croatia go in front.
Ireland defender Stephen Ward inadvertently sliced his clearance into the path of Jelavic, who was behind the defense and only needed to prod the ball past Given from close range.
It was a bad break for the Irish and things got even worse in the opening minutes of the second half.
Mandzukic turned a header toward goal that struck the right post, but as Given dove to stop it, the ball struck the 'keeper in the head and redirected into the net.
It was a play that summed up the match for Ireland, whose best scoring chance after the break came in stoppage time when Keith Andrews nodded the ball inches past the post.
Croatia will attempt to make it two wins from two games when the team faces Italy in its next match, while things only get tougher for Ireland as a contest with Spain awaits next.