Francis told the rugby players in town for a match on Saturday that theirs was a "tough" sport but one without violence, where individual and team greatness complement one another. Francis also met Friday with FIFA chief Joseph Blatter.
"We spoke the same language and it was language of football," Blatter said. "It was really a meeting between two sportsmen and two football fans."
Blatter said he responded to the pope's request for FIFA to help the favelas, or slums, of Rio de Janeiro during the 2014 World Cup, with a promise to "do what we can."
"We cannot do everything," Blatter said.
The soccer-mad Francis, a longtime member of his beloved San Lorenzo club in Buenos Aires, has amassed an impressive collection of soccer jerseys as gifts from visiting teams and players.
The two also unwittingly wound up confronting the relative strength in the numbers of active participants in their institutions, with those involved in football, including players and their families, slightly outnumbering Roman Catholics worldwide.
"We have 1.2 billion people and (the pope) said, 'I have no more than 1 billion,'" Blatter said with a laugh.