Lionel Messi not winning the World Cup with Argentina would be unfair, according to goalkeeper Oscar Ustari.

Messi has won everything on offer during his time as a Barcelona player – the Champions League, LaLiga, UEFA Super Cup, Club World Cup, Copa del Rey and Supercopa de Espana.

However, the six-time Ballon d'Or winner is yet to taste senior success in an Argentina jersey following a runners-up finish at the 2014 World Cup, having also reached back-to-back Copa America finals in 2015 and 2016.

A two-time Argentina international, Pachuca goalkeeper Ustari warned against doubting captain Messi – the country's all-time leading goalscorer.

Son días complicados para todo el mundo. Vivimos preocupados por lo que está ocurriendo y queremos ayudar poniéndonos en el lugar de aquellos que peor lo están pasando, o bien porque les afectó directamente a ellos o sus familiares y amigos, o porque están trabajando en primera línea para combatirlo en hospitales y centros de salud. Quiero enviarles mucha fuerza a todos ellos. La salud debe ser siempre lo primero. Es un momento excepcional y hay que seguir las indicaciones tanto de las organizaciones sanitarias como de las autoridades públicas. Sólo así podremos combatirlo de manera efectiva. Es el momento de ser responsable y quedarse en casa, además es perfecto para disfrutar ese tiempo con los tuyos que no siempre se puede tener. Un abrazo y ojalá consigamos darle vuelta a esta situación cuanto antes. #QuedateEnCasa #StayAtHome

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"I have no doubt that if Messi isn't world champion, football will be unfair," Ustari told Radio Mitre.

"Doubting Messi is nonsense. Things can go well or not, but I can tell you that I have seen him crying like a child because of what was happening in the national team. It's very difficult to be in his shoes.

"I remember that in the 2011 Copa America [Argentina were eliminated by Uruguay in the quarter-finals] I was recovering from my knee and, when they lost, I went to see Messi at the Ezeiza venue and I saw him like I had never seen him before, devastated."