Argentina is gripped by a debate over superstar Lionel Messi, who was devastated by losing the Copa America final and has reacted by withdrawing into shocked isolation.

Some obervers in his home country say criticism fired at Messi could force him to take a break from national duty.

The 28-year-old soccer genius left the pitch ashen-faced after Argentina lost the Copa America to Chile in a 4-1 penalty shootout in Santiago on Saturday.

The scenes were reminiscent of last year's World Cup final when Germany beat Argentina in extra time. Messi, who first tasted a major defeat in 2007 when Argentina lost 3-0 to old rival Brazil in the Copa final, posted a statement on his facebook account on Monday night.

"There's nothing more painful in football than losing a final," he said. "But I don't want to leave it any longer to say thank you to everyone who has always supported us and continued to during the tough moments."

Despite his huge success with Barcelona, Messi is now going through tough moments - as is a country that has not won a major title for 22 years.

Spanish media reports said Messi turned down the player of the tournament trophy. The trophy was withdrawn before the presentation ceremony in Santiago.

Break from the blues

Messi and the other Argentine stars were criticized by the country's media for their performance. Members of his family were also abused by Chilean fans at the match, according to Argentine media.

Some observers have warned that Messi could walk away from the national side.

"Desolate after another lost final, and especially by the tough criticism, Messi could take a break from the national team," the Ole sports daily reported on Tuesday.

Television talk shows are now dominated by what is wrong with Messi and the national team. Why does he not dazzle for Argentina like he does for Barcelona?

"One day this boy is going to get tired and will not want to come to play for the team," former Argentine international Matias Almeyda, now coach of the Banfield club, told Fox Sports television.

"He was criticized for not singing the national anthem. He is always being criticized for something. But he's the best player in the world and he is not treated in the way he deserves."

Argentina Football Association president Luis Segura has been shocked by the suggestions.

If Messi left, Argentina could lose out on key earnings from friendly internationals in which he is often under contract to play.

"I don't understand the people who criticize him," Segura said. "Messi suffers as much as the supporters from not winning a title."

Messi had a brilliant season with all-conquering Barcelona but Almeyda said "it is very difficult (for Argentine players) to repeat for the national team what they do for their clubs".

Messi has already scored more goals for Argentina than beloved icon Diego Maradona. But he has never won a World Cup for Argentina, like Maradona did in 1986.

His next chance could come in Russia in 2018. Messi will be 31 then and that could be his last hurrah.

After the Santiago final, Messi took refuge at his home city of Rosario, 400 km from Buenos Aires, as he traditionally does during Spain's break from soccer.

Around him, the criticism goes on against the team and its coach Gerardo Martinez. Some Argentines are even using social media to say that "Maradona = Messi and Javier Mascherano".