Argentina reach World Cup semi-final after fighting back to defeat Wales

Wales will kick themselves all the way home from the Rugby World Cup after a frustrating knockout defeat that will sting for ages. After half an hour they had looked all but certain to make the last four, with Argentina seemingly down and out. By the end, it was an entirely different story, two Puma tries in the last 12 minutes savagely ending Welsh hopes and dreams.

It was a tale of two huddles: a tight, solemn circle of red while barely 10 metres away the winners bounced up and down in a pale blue and white wonderland. The hymns and arias had long since fallen away as Wales, 17-12 up entering the final 15 minutes, found themselves grimly reeled in and unable to pull off another of their trademark great escapes.

Related: Warren Gatland laments Wales’s failure to handle ‘disruptive’ change of referee

It was particularly tough on young Sam Costelow, who had an attempted pass smartly intercepted by an onrushing Nicolás Sánchez for the clinching score three minutes from time, but Wales should have had the game all but wrapped up by half-time. They had been leading 10-0 after half an hour, only to lose focus and impetus and hand the Pumas an unlikely lifeline, with Tomos Williams’s neatly taken 55th-minute score ultimately not enough to tilt the outcome back in their favour.

So much for Wales’s ambitions of a third semi-final appearance in four World Cup campaigns under Warren Gatland. While Argentina will point to their powerful finish, with replacement prop Joel Sclavi contributing a gamechanging try three minutes after coming on, Wales paid a heavy price for their first-half largesse.

With the line beckoning, Josh Adams shelled an inside ball that would have yielded his side’s second try and Dan Biggar, uncharacteristically, missed a straightforward penalty he would usually slot in his sleep. Three lineouts also went astray in the Pumas’ 22 and attention will also be focused on the pivotal moment in the second half when Nick Tompkins was poleaxed by an Argentinian shoulder at a ruck.

Karl Dickson, on as a replacement referee after Jaco Peyper strained a calf in the first quarter, decided Tompkins was falling before contact and opted not to show a card of any colour. Justice did not feel as if it had been done, however, when the centre was forced to leave the field for a head injury assessment just as the game was reaching its critical phase.

On a seductively clear, warm Mediterranean afternoon, it was a massive moment. Before kick-off, Gatland had stood impassively in the 22, looking every inch a man at home in this kind of high-pressure environment. So, initially, did his players. As against Australia in the pool stages they soaked up some early pressure and then went straight up the other end to score via a midfield bust and a simple inside ball from Gareth Davies to the supporting Biggar.

The fly-half then slotted another three points and, at 10-0, everything seemed to be going to plan. Argentina can look good with ball in hand but the foundations of their game are far from infallible. As the penalty count escalated and Wales cranked up the scoreboard pressure there were echoes of the Pumas’ opening pool game against a 14-man England at the same venue, when Michael Cheika’s side fell way short of the required standard.

Related: Dan Biggar, the battered Welsh dragon, has flame extinguished by Argentina | Andy Bull

It did not improve the Pumas’ humour, either, when Peyper handed over the whistle to Dickson. Little did they know that, not unlike the Welsh jersey numbers that peeled off in the first half as if they were made of non-stick felt, things would soon change. Wales grew increasingly distracted even before a mass altercation sparked by a body check by Adams on the Pumas’ scrum-half, Tomás Cubelli, with the ball having just gone dead.

Adams was adjudged to have made a vague attempt to wrap his arms and players on both sides also escaped any sanction for the mass melee that followed. It was indicative of Wales’s gradual loss of tactical control, even if their 10-6 interval lead was still statistically encouraging. The team trailing at half-time had previously won one of the previous eight fixtures between the sides.

Welsh fingernails, even so, were now being anxiously nibbled. By now, Emiliano Boffelli had found his kicking boots and a long-range penalty put Argentina ahead for the first time. Cue Williams, whose golden moment could not have arrived at a seemingly more opportune moment. There had been precious little on with Biggar having just run down a cul-de-sac but Williams glimpsed an opportunity to nip between two forwards and score under the posts.

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It was to be a short-lived reprieve. With Tompkins having been led away for his head injury assessment and Wales under the pump, Argentina sniffed their chance. A prolonged period of forward pressure resulted in Sclavi’s close-range score and Boffelli’s conversion put his side two points ahead with 10 minutes left.

The rest was red-raw Welsh agony. Maybe they could have set up one more opportunity but Costelow, aiming to ship a short ball to Tompkins, could only watch in horror as Sánchez materialised from nowhere to pick off the pass. Boffelli did the rest to send Argentina bouncing into the semis.