Sixteen-year-old Simone Biles made everyone forget the United States came to the world championships without the defending and Olympic champions, beating teammate Kyla Ross in a nail-biting finish to win the all-around gold medal on Friday.
Biles and Ross were neck-and-neck throughout the evening, with Ross matching Biles' athleticism and power with grace and elegance, leaving it to the concluding floor exercise to separate the two.
Biles jumped, twisted and strutted at will, and it turned into a victory dance in front of the many thousands clapping to her music in the Sports Palace.
"On floor I just have a lot of fun. That is the main key," Biles said.
Aliya Mustafina of Russia, the 2010 champion, took bronze. Defending champion Jordyn Wieber and Olympic gold medallist Gabby Douglas skipped the event.
Biles also qualified for all four apparatus weekend finals — the first female U.S. gymnast to do so since Shannon Miller in 1991.
Ross, who is also 16, led by a feather light .016 points going into the floor routine, but there Biles turned on the power to win. Biles scored 60.216 points, while Ross ended with 59.332. Mustafina had 58.856.
Together, Biles and Ross showed the strength in depth the U.S. team has early in the new Olympic cycle ahead of the 2016 Rio Games.
"We are hoping that these girls keep going all the way to the Olympics," U.S. women's coach Martha Karolyi said.
And as good friends, Biles and Ross can go a long way together.
"We don't really think ... of each other like competition," Biles said. "So we try to have it the best way and think 'wow, this is worlds, we still cannot even believe it."'
From the outset, Biles set the challenge, picking a vault with extreme difficulty which needed only a small corrective step at the end, giving her a big score. Ross looked all smoothness and grace on hers but her lower degree of difficulty made that easier.
The two Americans were leading after the first apparatus while Mustafina immediately had a huge task ahead since she had to make up almost a full point.
Ross made it even tighter with a flowing performance on the uneven bars to trail Biles by less than a tenth of a point halfway through the contest, with Mustafina in striking distance, half a point behind.
Then it came down to the balance beam, so often a decider in major championships.
Biles was out first and showed poise belying her age, nailing all the big jumps. Ross did even better, though, and barely moved in front with a 44.999-44.983 edge.
It set up the perfect finale for a nation that had dominated the women's event all week.
Even if Ross looked near flawless in her floor routine, her starting difficulty was much lower than the one Biles put on and it helped make the difference.
"They did everything they were prepared for," Karolyi said. "Lot of psychological work. Building up their confidence level is the key."