Messi can't cover up Argentina's defensive flaws in Brazil defeat

At times, there was more heat than light, and there were moments when referee Roddy Zambrano seemed out of his depth and on the verge of losing control.

But at least the knockout stages of the 2019 Copa America have thrown up a blood and thunder match, with two teams looking to attack, and the drama was not restricted to the cruel, cheap finale of the penalty shootout. Old South American rivals Brazil and Argentina produced a game to live in the memory. In the end, Brazil were predictable 2-0 winners, but Argentina pushed them much further than most had expected.

Argentina have grown throughout the competition. The shambles of the opening defeat to Colombia have given way to something more coherent, a team with some basic idea of what it is trying to do. The original idea of caretaker coach Lionel Scaloni -- rapid transitions to the wings -- never fitted a side in which Lionel Messi is the leading light. During the course of the tournament, the team have started to develop a circuit of passing through the middle, and in Belo Horizonte against Brazil, they produced by far their best display in the Copa, both as a consequence of a gradual development and because the occasion demanded nothing less.

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That said, they remain a team with limitations. After their 2-0 quarterfinal win over Venezuela, two observations seemed pertinent: They would surely struggle to keep a clean sheet against Brazil, and it was hard to see them winning the semifinal without a top performance from the previously disappointing Messi. The team captain would again have to produce heroics to cover up the defensive cracks and lack of pace and quality along the back line.

In large part, that was the story of the game. Messi & Co. had their moments. First, his free kick was glanced on by Sergio Aguero and came back down off the underside of the bar. Later he latched on to a blocked shot from Lautaro Martinez and sent a volley off the near post. A free kick from the left edge of the area was dinked over the wall, only for keeper Alisson to make a difficult save look easy, and finally there was one glorious moment when Aguero, Martinez and Messi combined and slipped in midfielder Rodrigo De Paul. The Udinese man blasted over when the quality of the move deserved a goal -- as did the team's overall performance.

Argentina worked hard to stay compact, despite fielding Messi plus two out-and-out strikers. Aguero and Martinez worked hard to get behind the line of the ball, and the team gave everything in a quest to force the Brazilians back. Here were some excesses of enthusiasm; both full-backs received yellow cards early, and Leandro Paredes, who has taken over extra defensive responsibilities as the holding midfielder, was lucky not to join them. But with a mixture of fire, hard work and skill, Argentina played an equal part in the game without ever being outgunned.

But the defence remains a time bomb. For the first goal, Dani Alves was able to take out three opponents, opening up space for Roberto Firmino to get in behind down the right and cross low for Gabriel Jesus to turn in from point-blank range. The second, when Argentina were caught on the counter-attack in the 71st minute, was a symbol of the problem that has dogged the team in recent times -- a desperate lack of defensive pace. Gabriel Jesus burst past both centre-backs -- German Pezzella and Nicolas Otamendi -- with embarrassing ease before returning the favour and squaring for Firmino to do the rest and clinch the game.

This defeat is no disaster for Argentina, as they certainly weren't humiliated. Scaloni is a caretaker coach who has renewed an aging squad. After Saturday's third-place match, a new era will begin, a new coach will be selected, and a new project will be initiated.

Some of the players developed by Scaloni will have an important role to play, and the urgent priority is to come up with some new defenders and a goalkeeper who is good with his feet. Tottenham's Juan Foyth shows potential -- thrown in at the deep end, he did well in his natural position of centre-back vs. Qatar and came through the challenge of playing right-back against dangerous wingers the next two games. He was partially at fault for the second goal, making the schoolboy error of stopping when he thought he heard a whistle, but there is no doubt that he is one for the future. Plenty of others are needed.

Brazil's timescale, meanwhile, is very different. Argentina must think long-term, while Brazil's sights have never been set beyond Sunday's final, hence the decision to recall 36-year-old Alves as the team captain and starting right-back. He will surely not be around for the next World Cup, but he is vital now and was a strong candidate to win man of the match against Argentina. His role in the opening goal was a perfect illustration of what coach Tite is looking for from his full-backs. Brazil play with wingers, so there is no need to duplicate their function. Instead, the full-backs are expected to construct the play from inside, and Alves did just that, cutting in and opening up the corridor for Firmino down the right and then slipping him a perfectly weighted and timed pass.

Tite will also be happy with the exchange of positions by Firmino and Gabriel Jesus, who swapped roles and confused the Argentina markers. It is the type of move he has spent much of the past year trying to prepare, and it came off at a key moment in a huge game.

There are causes for concern, though. His side were pushed back for long periods, as Casemiro was unable to get a grip on the midfield, and the team were often too slow to move the ball. Had they done it better, they could have further exposed the Argentina defence.

At the moment, though, the key cause for concern is the 24-hour wait to find out the identity of Sunday's opponents. Brazil have a 100 percent record in home Copa Americas, and they are one game away from extending that record to five for five when on home soil.