Two-try man-of-the-match Keiran Williams consigned the Ireland Under-20s to their first defeat of the season as Wales triumphed 41-27 in a pulsating eight-try contest.
The Under-20 Six Nations has mirrored the senior tournament in that England – thanks to tonight's 33-5 bonus point win over Scotland – have secured the title with one round still to play.
Despite a mostly positive performance, Ireland's title hopes came to an end in Colwyn Bay which the Wales U-20s have turned into something of a fortress in recent seasons.
Centre Kieran Williams' try on the stroke of half-time gave the free-scoring hosts a 24-13 lead at the break, with Ireland captain Calvin Nash having crossed in brilliant fashion for a sixth-minute opener after combining out wide with Jordan Larmour.
Larmour, who was so effective in attack against France, continued to pose a threat off limited ball but it was the Irish pack who grabbed the game by the scruff of the neck in the third quarter.
Having gone 14 points behind, Caelan Doris and his fellow forwards slowed the tempo and began to dominate the forward exchanges. Their comeback began with Tadgh McElroy being driven over, to the right of the posts, from a lineout maul.
Out-half Bill Johnston, who kicked 12 points on the night, converted the hooker's third try of the tournament and also added the extras to flanker Paul Boyle's 52nd-minute effort following a series of punishing pick and goes.
Ireland were back level but replacement Conor Fitzgerald's sin-binning on the hour mark was particularly costly, Williams catching the eye once more with an excellent bonus point try from a midfield burst.
Nigel Carolan's youngsters dug in and very good work in the scrum did briefly get them back into scoring range. However, time was not on their side and Wales wrapped up with the victory with a late pushover effort from replacement Jack Pope.
The 14-point loss leaves Ireland fighting for the runners-up spot now as they look to get back to winning ways at Donnybrook on St. Patrick's Day (kick-off 6pm) and deny England an U-20 Grand Slam.
The opening half whizzed by at Parc Eirias and Wales were first on the scoreboard courtesy of a penalty from number 10 Ben Jones. Just four minutes later, some lovely link-up play between the counter-attacking Larmour and Nash up the left wing saw the latter outpace the Welsh cover for a skilfully-crafted converted try.
Back on the defensive, a horrid bounce from a Welsh kick evaded Nash and Corey Baldwin was almost over for an opportunist try. Wales pressed from two scrums in the 22 and although the Irish eight stood their ground, a quick tap and Jones' ability to suck in two defenders saw him feed hooker Corrie Tarrant for a slick seven-pointer in the 12th minute.
The home side really had the bit between their teeth, their eagerness to run and move the ball at pace seeing Ireland caught narrow and Cameron Lewis' basketball-style pass, which looked slightly forward on the replays, sent scrum half Dane Blacker charging clear for try number two.
Ireland's response was encouraging, albeit that Johnston hit the post with a penalty effort. Dynamic number 8 Doris broke strongly from a scrum and a bout of forward pressure should have led to a try but returning centre Jack Kelly knocked on to the left of the posts.
Two successful penalties from Johnston after 25 and 37 minutes closed the gap to 17-13, the Tipperary youngster punishing Rhys Carre for dropping his bind in the scrum and centre Williams for taking out Jonny Stewart at a ruck straight in front of the posts.
In between, Ireland lacked the necessary composure in try-scoring situations. Strong carries from Gavin Coombes and Oisin Dowling had the try-line in sight, but Wales managed to isolate the latter and win a clearing penalty. A knock-on at the breakdown blighted another Irish surge soon after.
Larmour had two jet-heeled runs, carrying more of a threat as half-time approached. However, Wales produced a late sting in the tail when the excellent Williams stepped past Tommy O'Brien's attempted tackle and darted to the whitewash for a real sucker-punch score.
When Jones converted and then fired over a penalty early on the resumption, it looked like a long second half lay ahead for Ireland. Crucially, they responded with that muscular maul score from McElroy after Johnston's reliable boot had set up the lineout opportunity.
Good patient build-up play from Ireland saw them continue to take Wales through the phases up front, keeping the momentum up as Wales' penalty count increased. Johnston did well to gobble up an overthrown lineout, the Irish loose forwards picking up the baton with a series of ground-gaining carries that ended with Gorey native Boyle burrowing over from a couple of metres out.
Johnston sent the left-sided conversion through the uprights for a 27-all scoreline, and the vocal home crowd then played their part in rallying Wales. The hosts recovered well with Jones and increasingly influential lock Alex Dombrandt spearheading a cracking break. Baldwin was up in support to finish it off, however referee Christophe Ridley eventually ruled it out for a forward pass.
As the Welsh backs began to threatened with more regularity, Shannon clubman Fitzgerald was pinged for successive penalties – the second one after he failed to retreat the necessary distance for a quick tap penalty – and Ridley reached for his yellow card. The subsequent Welsh maul was well defended and a big tackle from second row Dowling forced an Irish lineout.
14-man Ireland cleared their lines but Jones then used set piece possession to send Williams scampering past two defenders and in under the posts for a key score. The conversion was added before a spate of handling errors prevented both sides from building pressure on the front foot.
The Irish backs gave a glimpse of their attacking qualities with a Larmour break from the 22 and the full-back's offload sent O'Brien speeding up the touchline. Wales scrambled back and successfully absorbed some scrum pressure before sealing the deal in the dying embers. A penalty was tucked away towards the left corner and reserve lock Pope piled over from a well-orchestrated maul.
TIME LINE: 2 minutes – Wales penalty: Ben Jones – 3-0; 6 mins – Ireland try: Calvin Nash – 3-5; conversion: Bill Johnston – 3-7; 12 mins – Wales try: Corrie Tarrant – 8-7; conversion: Ben Jones – 10-7; 15 mins – Wales try: Dane Blacker – 15-7; conversion: Ben Jones – 17-7; 19 mins – Ireland penalty: missed by Bill Johnston – 17-7; 25 mins – Ireland penalty: Bill Johnston – 17-10; 37 mins – Ireland penalty: Bill Johnston – 17-13; 40 mins – Wales try: Keiran Williams – 22-13; conversion: Ben Jones – 24-13; Half-time – Wales 24 Wales 13; 43 mins – Wales penalty: Ben Jones – 27-13; 45 mins – Ireland try: Tadgh McElroy – 27-18; conversion: Bill Johnston – 27-20; 52 mins – Ireland try: Paul Boyle – 27-25; conversion: Bill Johnston – 27-27; 60 mins – Ireland yellow card: Conor Fitzgerald; 62 mins – Wales try: Keiran Williams – 32-27; conversion: Ben Jones – 34-27; 79 mins – Wales try: Jack Pope – 39-27; conversion: Ben Jones – 41-27; Full-time – Wales 41 Ireland 27
Referee: Christophe Ridley (England)