The first half saw few openings as the hungry opponents battled it out, with the sapping humidity in the Komaba Stadium not helping proceedings.
Italy defender Linari broke the deadlock by crashing a powerful free-kick into the top corner from all of 30-yards giving goalkeeper Daniele no chance.
Brazil started the second half with renewed vigour and Ketlen, twice, as well as captain Thais Guedes, each pushed efforts narrowly wide within a 90-second period.
The Azzurrine’s hopes suffered a blow as substitute Federica Di Criscio was dismissed with a quarter of an hour remaining after two yellow cards in quick succession.
Brazil increasing dominated possession and their opponents' under-pressure defence eventually gave way, though it took a stunning individual strike to do so.
Two minutes into injury time Amanda burst into the penalty area on the left, flicked a ball over a defender, before unleashing a volley over the stranded goalkeeper from an acute angle for a goal worthy of any stage.
"We felt confident against Brazil, for no special reason,” said Italy coach Corrado Corradini. “We know Brazil is very technical, very fit and strong, but we just believed we could stop them. We know we are not strong mentally, there are a lot of weaknesses."