Thursday, Aug. 23, is the 10th anniversary of Lionel Messi's biggest triumph with Argentina.

In 2005, he helped his teammates overcome Nigeria to win the Under-20 World Cup and then, three years later -- a decade ago -- against the same opposition, Argentina won the Olympic gold medal.

Since then it has been a case of finals and frustration. Argentina fell at the last fence in the 2014 World Cup, the 2015 Copa America and the 2016 Copa America Centenario. But, in hindsight, it would appear that Messi's best chance of lifting the big prize with his national team had already come and gone before that Olympic gold.

The 2006 World Cup in Germany was the competition where Argentina had their best, most solid team of recent years, but they lost in the quarterfinals on penalties to the hosts -- a match they really should have won, where Messi was left uselessly kicking his heels on the substitutes' bench.

Might that superb right-footed goal in Russia -- once more against Nigeria -- be his last contribution to a World Cup? Might we never see the 31-year-old again in an Argentina shirt?

The only thing clear at present is that Messi is taking a break from the national team. Presumably the Argentine Football Association would be keen to have him back; they can charge much more for friendlies with Messi on the field. That said, they also have to deal with the long-term problem, the failure that has blighted Messi's time playing for Argentina -- the collapse of the youth setup.

Between 1995 and 2007, Argentina won the U20 World Cup on five occasions. Ever since, though, their youth sides have been very poor, and this has filtered through to the senior ranks. There has been a disastrous lack of renewal in certain positions. Fourteen of the 23-man squad that went to Russia were over 30, and there was the conspicuous absence of top-class performers in goal, full-back, centre-back and central midfield.

There is major rebuilding work to be done. FA boss Claudio Tapia announced that "we are going to take a semester to find the man to take charge. More than anything, we are in search of a project. We will take as long as necessary to make a good choice."

In the short term, ex-international right-back Lionel Scaloni has been given the job on a caretaker basis. He has clearly been given a brief to bring in young players. In early August, Tapia said that "we thank this generation and begin a new era with the national team." Thus, It is not just Messi who does not figure in the 29-man squad Scaloni has named for next month's friendlies; Sergio Aguero, Gonzalo Higuain, Angel Di Maria and Nicolas Otamendi have also all been left out, with Javier Mascherano having retired from international football. Defender Gabriel Mercado, 31, is the only outfield player over 30 to be named.

Scaloni, it seems, has pretensions that go beyond merely giving a chance to some youngsters. "We believe," he somewhat grandly announced, "that football is on the way to becoming more direct, and that is the type of football that we like -- winning possession and arriving as soon as possible at the opposition's goal. In the World Cup it was evident that the teams that won were those who were rapid on the transition; France and Croatia were winning the ball and in a position to shoot in three or four seconds. That's the way football is going, it's what I like and this is the moment to implant it in Argentina too."

It is Scaloni's way. But, used to something more elaborate with Barcelona, it might not be Messi's. Which means that Argentina's caretaker coach might be relieved that he will not have Messi around next month. It might not be easy to force Messi to travel by the route one way that Scaloni is proposing.

This, though, is a short-term hiccup. The relationship between Lionel Messi and the Argentina side is one for the next permanent coach, whenever he is appointed. Unless, of course, Scaloni's quest to implant a direct style is part of an improbable bid to win the position.

Either way, times look to be changing with La Albiceleste.