But Nikica Jelavic restored Croatia’s advantage just before half-time after Stephen Ward’s hashed clearance.
And after Mandzukic’s header hit the post and then Given to go in just after the break, Giovannia Trapattoni will have been left wondering if the Republic’s Euro dream is already over with Spain and Italy awaiting them in their remaining Group C games.
It was a nightmare start for Ireland in every sense.
Ivan Rakitic’s corner was not fully cleared and when the loose ball was eventually dinked back to Darijo Srna, his deflected cross fell to Mandzukic to steer a header past the scrambling Given from 12 yards.
Trapattoni’s men had it all to do but they responded well to going behind with Damien Duff and Kevin Doyle linking up well.
And it didn’t take them long to level things up after Vedran Corluka shoved Doyle and gave away a free-kick.
The former Spurs and Manchester City full-back then failed to deal with Aiden McGeady’s floated ball, allowing St Ledger to nip in and header past Stipe Pletikosa from close range.
If Ireland had come back strongly after falling behind, Croatia also livened up after conceding as Ivan Perisic smashed a 25-yarder at goal which was well saved by Given to his left.
Perisic struck wide with a long-range volley but the Irish were matching their opponents — Doyle in particular looking a handful for the Croatian backline.
Ireland’s defence had looked strong under a barrage of crosses but it fell to pieces just before half-time allowing Croatia to retake the lead.
Luka Modric rifled an effort goalwards but Ward made a mess of his clearance, slicing only as far as Jelavic who coolly lifted the ball over Given from five yards out.
The Everton striker was stood offside as Modric struck his initial shot but Ward and Ireland could have no real complaints.
If conceding before the break was bad, conceding straight after will have been equally as painful for Ireland’s travelling support.
Perisic was given time to find Mandzukic whose header struck the post but rebounded off the head of the helpless Given and into the net.
Trapattoni threw on Jon Walters and Simon Cox for Doyle and Aiden McGeady and the changes had the desired effect with Ireland denied what looked a certain penalty just past the hour mark when Schilderfeld tripped Robbie Keane from behind.
But referee Bjorn Kuipers told Keane to get up, causing tempers to flare briefly between the two sides.
Hrvatska protiv Irske 3-1 10/6/2012 Jelavić i Mandžukić sve ciljeve ističe euro 2012
Croatia v Ireland 3-1 10/6/2012 Jelavic & Mandzukic
Croatia v Ireland 3-1
Croatia v Ireland 3-1
Croatia v Ireland
Croatia 3-1 Ireland