Barcelona and Argentina's all-time leading goalscorer, Messi has constantly been compared to past greats Pele and Diego Maradona, while going head-to-head with Real Madrid rival Cristiano Ronaldo.

But Pope Francis – the leader of the Catholic Church and a renowned San Lorenzo supporter – threw his support behind countryman Messi.

"For me, [Lionel] Messi is better than Maradona and Pele," Pope Francis was quoted as telling young men and women participating in World Youth Day.

Messi endured a difficult Copa America Centenario, stunning the world when he announced his retirement from national team duty after Argentina lost to Chile on penalties in the final.

The 29-year-old, though, finally returned to the pitch as Barcelona kicked off their LaLiga preparations with a 3-1 win over Celtic in the International Champions Cup on Saturday.