Brazil caused a major surprise by earning a place in the Women's World Cup final at the expense of USA.
Marta celebrates doubling Brazil's advantage in Hangzhou
The US, who had not lost for 51 games, went a goal behind when Leslie Osborne inexplicably headed into her own net.
The superb Marta then cut inside and drilled in, before the US were reduced to 10 when Shannon Boxx was unlucky to be sent off for a second booking.
Christiane slotted in and Marta sealed it with a brilliant solo goal, cutting in from the left and rifling home.
The victory sets Brazil up for a final clash with Germany in Shanghai on Sunday, with live coverage on BBC Two at 1245 BST and live updates on this website.
The pre-game talk was almost all about USA's sensational decision to axe number one goalkeeper Hope Solo in favour of 36-year-old veteran Briana Scurry.
The spotlight was certainly on Scurry and she failed to come through her first test, flapping hopelessly at a free-kick punted into the box, only to be let off the hook when Elaine blazed over from six yards.
But when Brazil did take a surprise lead, there was not much Scurry could have done about it.
Formiga swung a corner in from the left and Osbourne, hesitating over how to clear her lines, unfathomably stooped to head the ball into her own net.
If Scurry was blameless for the first, she could - and perhaps should - have done something about the second goal.
Marta collected the ball and cut in from the right and drilled a shot towards the bottom corner, Scurry getting down to her near post but failing to get sufficient contact on the ball to prevent it going in.
By first-half stoppage time, USA's hopes lay in tatters. Boxx was ludicrously adjudged to have fouled Christiane and she was sent off for her second booking.
The second half was as one-sided as you could imagine the semi-finals of a World Cup to be.
Brazil tore US's 10 women to shreds, Maycon twice using her blistering pace to sprint clear, but twice drilling wide of Scurry's far post.
The third goal came when Formiga got away down the left and crossed to find Christiane on her own 12 yards out. She steadied herself and coolly slotted low into the corner.
Marta produced some magic down the left to set up Christiane again only for her shot to curl wide, before Marta scored a goal that will live long in the memory.
She magically flicked the ball around Tina Ellertson with the heel of her left boot, cut in past one defender from the left and drilled low under Scurry.
Christiane rifled against the post with the clock ticking down as the Brazilian bench began their celebrations in earnest.