The closest Messi has come to being a FIFA World Cup winner was when Argentina was beaten by Germany in the 2014 final.

His unprecedented seven Ballon d'Or successes underline Messi's individual greatness, but he is missing the most valued team prize of all.

Winning the Copa America with Argentina last year gave him a first major title in senior international football, with Argentina getting the better of Brazil at the Maracana in the final.

Now aged 35, and in his final FIFA World Cup, Argentina captain Messi goes again, with former Barcelona team-mate Xavi strongly rating the Albiceleste's chances.

"Argentina and Brazil are a step ahead of everyone else," Xavi said.

"I see them very strong as a team, also with individual players, physical and in terms of tactics and strategy as well, they're two great teams.

"I think they're a step ahead of some of the best European teams right now. But in a World Cup you can never know. Everything can become complicated."

Xavi, a FIFA World Cup winner in 2010 with Spain and now head coach at Barcelona, added: "The European teams are very important: Spain, France, even England, have got very strong national sides, but I think Brazil and Argentina are a step stronger."

Brazil is a five-time FIFA World Cup winner but has not triumphed since Ronaldo's eight goals drove it to 2002 glory, while Argentina has carried off the trophy twice, in 1978 and 1986.

Messi, surprisingly, has never scored in the knockout rounds and is four goals behind Gabriel Batistuta, Argentina's FIFA World Cup record scorer (10 goals).

European teams have dominated the FIFA World Cup in recent times, with Italy, Spain, Germany and France winning the past four editions.