Man-of-the-match Messi scored a brace at the Nou Camp, one of them from the penalty spot, after the Africans went to the interval with a shock 2-1 lead.

The teenager told Argentinian TV station TyC Sports: "We did a great job in the second half, as we played as we have to play.

"We entered on the pitch too relaxed in the first half, without the pressure we use in the second half and Algeria surprised us.

"In the second half, we were the only team who really played on the field."

Argentina headed into this friendly after a 1-1 draw with Switzerland, with a performance that did not convince coach Alfio Basile.

But Basile was more impressed by what he saw on Tuesday evening in Spain.

He said: "I liked second half a lot. The team were superior to Algeria after the interval because the players who know what to do with the ball played together.

"We thought it would be easy but then they scored to us twice. These are things we have to correct."

Three goals conceded hinted at further work to be done ahead of the Copa America, which kicks off on June 26 and in which Argentina play the United States, Colombia and Paraguay in Group C.

"We all were needing a victory to go on improving and work calmer when we meet again all together," Messi added.

Debutant Diego Milito agreed with the Barcelona midfielder that his team-mates only came alive after the break.

"The first half was not good at all," the Real Zaragoza player said.

"We did not have the ball, we lost concentration for their goals, but then in the second half it was much better.

"I'm very happy for having had the opportunity to be part of the starting XI in the national team. I think that, overall, it was a positive game for us."

West Ham forward Carlos Tevez added that, on the pitch, the players are not thinking about being part of the Copa America squad:

"We only think about playing together, to get a football rhythm to make Argentina play at a high level as soon as possible."