Argentina will look to build on Friday's 2-0 win over Italy when they travel to Madrid to take on Spain in what is sure to be a star-studded international friendly.

They beat the Italians through goals from Ever Banega and Manuel Lanzini, but they did so without their talisman and all-time top scorer Lionel Messi.

Messi has been in sublime form for Barcelona in the 2017-18 campaign so far but sat out of the win in Manchester after revealing he'd been playing with an adductor muscle problem.

The five-time Ballon d'Or winner has trained ahead of the Spain clash, and manager Jorge Sampaoli will certainly hope to have his main man available for selection.

The Argentina boss has written a book, and ahead of its release in April, some preview passages have been handed out, and he had some pretty remarkable comments about Messi.

What Sampaoli has written about Messi

Sampaoli's words on Messi were given to the Viva, Clarin magazine, and the Argentine has opened up about the immense pressure he feels his captain is under to win the World Cup.

"Messi has a revolver put to his head called the World Cup." Sampaoli, who led Chile to the 2015 Copa America, explained, via Marca.

"And if he doesn't win it, he's shot and killed. As a result, he can't enjoy his talent. What I find is that the negativity surrounding international football damages Messi."

Does Messi need international success?

The main thing Messi's critics like to bring up is that he's never won a major tournament with his country, whereas Cristiano Ronaldo helped Portugal to win Euro 2016.

This is in spite of the fact that the little magician has guided Argentina to a World Cup final, two successive Copa America finals and Olympic success in 2008.

What else has Sampaoli written?

Sampaoli went on to praise Messi, but also interestingly suggested that he feels in less managerial control due to the sheer footballing magnificence of the 30-year-old.

"At this moment, I feel that I'm coaching the best player in history," the 58-year-old added. "This is a guy (Messi) who has stayed as the best in the world for ten years.

"It's difficult to assume a level of control when your leader (captain) knows he's better than you. He executes things like nobody else."

The ex-Sevilla manager also talked about Messi's incredible hat-trick in Ecuador which fired Argentina to the World Cup, as well as what it might take to win this summer's tournament.

"You have to find the best players and put them in their best position," stated Sampaoli. "Leo has to play like he does for his club. To put him into another structure (system) is madness.

"Against Ecuador, I was a bit strong in my tone suggesting that football owed Messi a World Cup, however, I knew he was going to appear for us at the vital moments."

What is YOUR opinion on all of Sampaoli's comments on Messi? Do YOU think Leo needs to win the World Cup, or is he already simply the world's best? Have YOUR say in the comments box below!