Alfredo Di Stefano has said he may have played street football with the new pope when they were youngsters growing up in Argentina.
Di Stefano said he was proud that the new pontiff, Jorge Mario Bergoglio, was from his home city of Buenos Aires.
Bergoglio was elected last week, and Real Madrid great Di Stefano, now 86, said their paths could well have crossed even though the new pope is ten years his junior.
In his column in the sports daily Marca, Di Stefano write that the pair had attended the same school and lived near each other.
"As you can imagine, his election filled me with enormous joy," he wrote. "The pope was probably one of those kids with whom I played football in the street.
"In the neighbourhood, we put together proper matches with everyone against everyone until it got dark.
"You'll have to ask him because at that time I was the famous one, from when I was very small, as I belonged to the River Plate youth academy. Everyone knew me."
Bergoglio is a fan of Buenos Aires club San Lorenzo and lives in "a permanent state of suffering" for them, it was reported last week.