And Liukin could finally breathe again.
"These are not machines," national team coordinator Martha Karolyi explained after her team overcame two big mistakes on the balance beam that could have cost them the meet.
The Americans finished with 184.4 points, beating defending champion China by .95 points for their second world title, and the first they've won on foreign soil.
Romania took the bronze after getting shut out of team medals last year for the first time since 1981.
Sacramone's winning floor exercise was as clutch as any pass ever thrown by Peyton Manning or basket made by Michael Jordan.
Sacramone powered through her flip combinations and landed without looking down, knowing she'd stayed inside the lines. And in the corners, there she was, seductively running her hand down her leg and flinging her arms open to the crowd.
"I told them, 'Everyone makes mistakes, but we still have one more event and it's one of our best events, so we might as well go out there and have fun and show everybody what we've got,' " she said.
The American comeback became necessary when Liukin, a former world champion on the beam, couldn't close out what had been shaping up as one of the best routines of her life on the sport's most difficult event.
The landing of her last flip resulted in an awkward thud. Later, she said she thought her foot slid halfway off the beam.
So instead of poising herself for a flip with 2 1/2 twists on the dismount, she settled for a back tuck.
She scored a 15.175, losing about a point off her usual mark.
This victory establishes the United States as the team to beat next year in Beijing.
"We're going into the Olympic Games as world champions," Liukin said. "How much better can you feel?"
