The US women's gymnasts delivered an astounding team score to vault them almost out of reach of the competition in their quest for gold on the first day of preliminaries at the Rio Olympic Arena. 

All five women earned a spot in either the all-around or event finals. In the case of Simone Biles and Alexandra Raisman, it was both. Biles performed to thundrous applause and her floor routine to the samba classic "Mas que nada" had the whole house clapping to the strong baseline. Her family watched from the packed stands. 

Who is Simone Biles? Learn more about the once-in-a-generation talent

The nerves were there

They were unmistakable. Unavoidable. Standing in the darkened tunnel before entering Rio Olympic Arena on Sunday night, the US team felt the pressure that comes not from outside expectations but those held within.

From left to right, Alexandra Raisman, Gabrielle Douglas, Simone Biles, Madison Kocian, Lauren Hernandez and coach Mihai Brestyan​ (Photo by Tom Pennington/Getty Images)

Then the lights came on, and just like that, the young women in the glittery red-and-blue leotards relaxed, then dominated on bars, on uneven bars and on vault and floor, too. Their score of 185.238 was nearly 10 points better than second-place China through four of the five subdivisions, a preposterous gap in a sport where the difference between first and second is measured in fractions. If the US had swapped its highest score for each event with its lowest, it would still be up by six points.

Low five for two of the fierce five (Photo by Tom Pennington/Getty Images)

National team coordinator Martha Karolyi has moulded the 'Fierce Five' into a global force. "It's never 100 per cent perfect but I think we showed that our gymnastics is of the highest level," she said. A level no opponent is close to reaching.

Meet the US team at Rio 2016

Three-time world champion Simone Biles led the way. Her score of 62.366 was well clear of team-mate Aly Raisman. So much for the butterflies in her stomach. "I do a very good job at hiding it," Biles said. "The team; we just calm it down."

Raisman, a three-time Olympic medalist four years ago, grabbed the second spot in the individual all-around for the Americans by edging reigning Olympic champion Gabby Douglas thanks in part to what Raisman called "the best bar routine of my life."

Grabbing a hold of her best (Photo: Getty Images/Tom Pennington)

Rules limit each country to two gymnasts per event in the all-around and event finals, meaning even though Douglas was third overall, she'll miss out on a chance to defend the crown she won at London 2012. Not that she was moping. When Raisman drilled her dismount on beam, Douglas rose from her chair and gave Raisman a hug.

Fist bump (Photo: Getty Images/Ezra Shaw)

Who can unseat the golden girls?

The top eight teams in qualifying move on to the team final on 9 August, when the US is expected to repeat the gold it won easily at London 2012.

China and Russia both struggled at times on Sunday, beset by mistakes they can't afford to make if they want to make the team finals anything more than a coronation.