And so the search for a first win over New Zealand goes on and on.
Ireland gave it everything they had and for over half an hour looked like they might be laying the foundation for an historic success.
But New Zealand, unbeaten when winning the first four world titles in this grade, took control and buried Irish hopes with a devastating show of strength and handling.
They will now go on with high expectation of lifting the World Rugby U-20 Championship for the first times since winning here in Italy in 2011, while Ireland will commence the battle for fifth place on Monday.
They will go into that series of games with a fair degree of hope despite the scale of this defeat at Stadio Luigi Zaffanella.
Waiting in the fifth place semi-final are Wales, who defeated Ireland 19-12 in the Six Nations competition last March, while Australia and Scotland will also vie for the honour of fifth and a seeding boost for next year's competition.
Ireland needed a bright start and they got it by retaining possession and doing the simple things well. They should have been further ahead by the time Joey Carbery got them off the mark after 16 minutes with a penalty from 40 metres.
Auckland-born Carbery, who moved to Ireland when he was 12, had earlier been off target with a 45-metre penalty from the left and also an effort from the right as Ireland took the game to the Baby Blacks.
And with Garry Ringrose making an impact from the start and flankers Josh Murphy and Rory Moloney, and winger Jacob Stockdale also to the fore, it was an encouraging start by Nigel Carolan's men.
Ringrose set the tone with a superb tackle on New Zealand full-back Luteru Laulala, a brother of former Munster centre Casey, which had the sizeable Irish crowd in good voice.
But, as New Zealand showed against Argentina, they punish teams if given an opening and they struck after 19 minutes with only their second attack of the night.
Scrum-half Te Toira Tahuriorangi came close to crossing when they peeled off the back of a strong maul, but Ireland defended stoutly. However a stunning long pass from out-half Otere Black finished off a stretched Irish defence for Tevita Li to score in the corner, with Ireland full-back Billy Dardis claiming he was impeded by Nathaniel Apa.
New Zealand, with gigantic No.8 Akira Ioane making his presence felt all over the field, got more of the possession and they extended their lead to 8-3 after half an hour when Black tapped over a penalty after Josh Murphy was penalised for not binding in a scrum.
Ireland lost captain Nick McCarthy to a shoulder injury five minutes before the break with Charlie Rock, who made his U-20 debut against Argentina last week, coming on.
New Zealand stretched their lead on the stroke of half-time when Irish prop Andrew Porter was penalised for kicking the ball out of the hands of scrum-half Te Toiroa Tahuriorangi and Black kicked from 35 metres to make it 11-3.
New Zealand went for the jugular from the restart. They went to the corner with a penalty just outside the 22 and were rewarded for the decision, going wide to the left and when they came back inside Li burst through Murphy's tackle to score under the posts.
Black converted to make it 18-3 and the game was gone from Ireland two minutes later when they were scrummaged off their own five-metre put-in and Blake Gibson scored in the left corner.
The conversion from Black extended the lead to 25-3. It suddenly became a damage limitation exercise from there as attentions turned to next Monday's clash in the battle for fifth to eighth places.
In fairness, Ireland never gave up and Murphy came close to scoring, but was denied by a combination of Gibson and Tahuriorangi when they finally got some ball going forward.
But the Baby Blacks defended their line to the hilt. After sustaining a lengthy period of pressure they countered and finished the game deep inside the Irish half to run out deserve winners by 22 points - the same margin that they beat them by a year ago in New Zealand in the battle for third place.
Some things never change.
New Zealand - L Laulala (M Hunt 55); V Tavae-Aso, Jack Goodhue (TJ Faiane 66), N Apa, T Li; O Black, T Toira Tahuriorangi (H Levien 69); I Tu'ungafasi (A Ross 66), L Polwart (R Riccitelli 52), A Moli (T Koloamatangi 52); Joshua Goodhue (M Dunshea 66), Hamish Dalzeil; J Blackwell, B Gibson, A Ioane (H Stowers 59).
Ireland - B Dardis (T Quinlan 48); J Owens, G Ringrose, S Arnold (F Cleary 71), J Stockdale; J Carbery , N McCarthy (C Rock 35); A Porter (L O'Connor 10-18 blood & 66), S McNulty (A McBurney 66), O Heffernan (C O'Donnell 52); D O'Connor, A Thompson (C Romaine 60); J Murphy, R Moloney, L Dow (S McVeigh 60).
Ref - Matthew Carley (England).