RIO DE JANEIRO • They may be on "autopilot", but they are not going to just do their routines at the Olympic gymnastics competition.
Americans Gabby Douglas and Simone Biles will go all out to win the all-round gold and their battle for success will be the main focus when the sport takes centre stage in Brazil from today.
Douglas, 20, is the reigning Olympic all-around title-holder and Games rookie Biles, 19, a three-time world all-around champion.
America are the reigning Olympic and two-time world team champions, with gold theirs for the taking with the duo in top form.
"We've done so many routines we're kind of on autopilot right now, so it's just like go, go, go, go," warned Douglas, bidding to become the first woman since Czechoslovakia's Vera Caslavska in 1968 to win back-to-back all-around Olympic titles.
Too young to compete in London four years ago, the acrobatic Biles has dominated since, winning 10 world titles and is the overwhelming favourite to be the star of the Rio Olympic Arena.
She snatched another gold at last year's world championships ahead of Douglas, and the 2013 and 2014 world titles, as her rival took time off after the London Games.
"We're so well prepared that we know what to expect of ourselves and our gymnastics once we go out there on the competition floor," said Biles, bidding to become the first woman to win five gymnastic gold medals at a single Olympics.
"It's the Olympics, but, if you think about it, your brain's going to fall out, you're going to freak out. So we are trying to treat it like a (national) championships."
Aly Raisman, 22, Laurie Hernandez, 16, and 19-year-old Madison Kocian, who shared the uneven bars world title last year, complete the five-woman US team.
Douglas and Raisman, winner of the floor gold in London, are the only two US gymnasts from the 2012 Games, with Douglas in Rio despite struggling in the Olympic trials.
"It's very good to combine experience with newcomers," said Martha Karolyi, 73, the US team's coordinator. "I always like that combination and I think it works this time.
"Traditionally Russia and China are the most competitive and Britain is coming up to challenge us."
Britain, the world team bronze medallists last year, are ready to challenge for a first women's Olympic team medal since 1928.
"We're stronger and better than we were four years ago," said Britain's Rebecca Downie. "We're hoping to get a medal as a team."
Russia's Aliya Mustafina won all-around bronze in London and, with China's Shang Chunsong and Giulia Steingruber of Switzerland, is expected to challenge for an all-around medal.
The reigning uneven bars champion is one of two members of Russia's silver-winning team from 2012, but without Olympic all-around silver medallist Viktoria Komova, Russia could struggle to match America in the team event.
"The Americans are so strong but we're confident of taking a silver," said China's Fan Yilin, 16, as the 2008 Beijing winners bid for a podium finish after finishing fourth in London.
Former gymnastics powerhouses Romania failed to even qualify a full women's team for Rio.
Women's qualifying begins today with the top 24 gymnasts advancing to Thursday's all-around final.
Eight nations qualify for Tuesday's team final, with eight gymnasts advancing to the apparatus finals - vault, uneven bars, beam and floor - from Aug 14-16.