A dramatic extra-time winner from substitute Lautaro Martínez ensured Argentina retained their Copa América title, edging out Colombia 1-0 in a thrilling game in Miami.

The Golden Boot winner’s cool 112th-minute strike settled a scintillating game, which had simply lacked a finishing touch until his arrival on 97 minutes. Martínez latched on to Giovani Lo Celso’s pass to dispatch the ball past a gallant Camilo Vargas in the Colombia goal.

It was the striker’s fifth goal of the tournament, in a game that also saw Lionel Messi forced off injured midway through the second period. Messi, in tears upon leaving the field, returned to lift the trophy for the third major tournament in a row, after a long drought that had threatened to define his international legacy.

The win gives Argentina a record-breaking 16th triumph at the Copa América, moving one clear of Uruguay. The scenes of joy on the pitch were marred, however, by harrowing scenes of organizational chaos outside Hard Rock Stadium, as police and stadium security struggled to cope with crowds massed outside, causing kick-off to be delayed by well over an hour.

The game scheduled for 8pm local time eventually began at 9:22pm and both teams were keen to compensate for lost time. Argentina’s Julián Álvarez, quizzically preferred to start ahead of Martínez in attack, scuffed a volley wide within 45 seconds. Colombia too showed an attacking intent that never yielded, with Jhon Córdoba’s smart chest and volley clipping the upright on six minutes.

The game was billed as a battle between veteran stars Messi and James Rodríguez, but it was Liverpool’s Alexis Mac Allister who expertly knitted together the holders’ play, while clubmate Luis Diaz’s powerful running drove an incisive Colombia forward. The ascendancy often teetered but the first period was edged by the underdogs, via some superb passing football. A searing 25-yard Jefferson Lerma drive forced Emi Martínez into a full-stretch save to tip the ball on to the post.

Messi looked certain to score on 20 minutes, but a swept effort from Ángel Di María’s pullback hit Álvarez on its way to goal. But Messi’s troubles began on 36 minutes when a challenge from Santiago Arias left him writhing on the ground clutching his right ankle. Seemingly, he was unable to shake off the injury.

As half chances continued to arrive for both sides in the second half – including a left foot strike from Di María, which forced a great save from Vargas – Messi stumbled to the ground on 65 minutes, without a challenge. The captain’s armband went to Di María, 36, playing his 145th and last game in an Argentina career spanning six Copa América tournaments. He too would leave the field in tears, albeit for different reasons, on 115 minutes.

Colombia had a strong appeal for a penalty rejected on 72 minutes as Córdoba and Mac Allister went for the same ball, before Argentina had the ball in the net through Messi’s replacement Nicolás González. The overlapping Nicolás Tagliafico was offside in the buildup.

González, who was more impactful than Messi, then rose high to head a Di María cross back across goal, but Álvarez failed to gamble on what would have been a tap-in as the 90 minutes ended. In extra-time, González forced a huge save after poking Rodrigo De Paul’s cutback goalwards. Vargas covered ground quickly to smother the ball on the goalline.

Even with the hot and humid conditions, it was an end-to-end and energetic extra-time period, where neither side seemed inclined to settle for penalty kicks. It felt as if a winner would arrive and before the end and Martínez duly delivered. Colombia contributed magnificently to the final, but are left to rue the absence of such a clinical finisher.

However, the scenes outside the stadium on Sunday evening threaten to overshadow the occasion completely. Organizational concerns have plagued the tournament, but the worst was saved for the final. A swell of thousands of fans remained crammed outside the stadium in scorching temperatures and humidity. Videos posted to social media showed some fans storming through security, others were trapped at the gates as children were lifted out of the chaos. Many fans looked visibly distressed by the ordeal. Videos showed people attempting to enter the stadium through vents or climb external fencing.

Stadium officials closed the gates to entry and moved to blame “thousands of fans without tickets attempted to forcibly enter the stadium, putting other fans, security and law enforcement officers at extreme risk”.

Tickets had changed hands for up to $2,000 on the secondary market on Sunday. But there was no proper stadium perimeter and no ticket pre-checks. As organizers pleaded with ticketless fans to leave the stadium, Fox Sports reported Argentina players’ families were among those caught in the chaos.

Between 8:15pm and 8:30pm the gates re-opened and the stadium rapidly filled. It had become too dangerous to keep the gates closed any longer. It’s not clear whether ticket checks happened but, but given how quickly seats were eventually filled, it seems in some areas of the stadium they did not.

The tournament was hosted by Conmebol with little input from officials on the ground in the US. But with the World Cup to be co-hosted by the United States in two summers’ time, important reviews will need to take place to make sure the scenes are not repeated under Fifa’s watch.

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