The USA women's gymnastics team repeated their London 2012 win in a display of verve and consistency so convincing that their floor exercise routines in the last rotation of the team final were more of an acrobatics-filled victory lap at Rio Olympic Arena tonight (9 August).

Simone Biles' samba-themed performance as the last competitor put the finishing touch to USA's trouncing of the seven other teams, who were left scuffling for silver and bronze.

A new piece of hardware to compliment the sparkling eye makeup of Simone Biles (Photo: Getty Images/Laurence Griffiths)

By a winning margin of more than eight points, USA won gold after they produced a dozen risky, forceful routines without sizeable errors. Biles credited the win to teamwork and diligence.

"We are so successful because we believe in ourselves," said the three-time world champion and the most decorated gymnast of all time who will also go for individual all-around Olympic gold on 11 August.

"It hasn't been easy, but we have done everything we could have done to get where we are," she said.

Gold for diversity at Rio 2016

The US posted a score of 184.897, more than eight points clear of silver-medallist Russia and nearly nine more than China, who took bronze. 

Chunsong Shang of China on the beam (Photo: Getty Images/Lars Baron)

Russia's lacklustre work on balance beam and floor exercise forced them to rally for a podium finish on their last apparatus, vault, where they jumped ahead of China to claim silver.

Second place was reward enough for Aliya Mustafina, one of three competitors who won silver at London 2012.

"We were expecting a good performance and we did it," she said. "It is obvious that USA are much stronger right now."

China took bronze.

A five's final farewell

Martha Karolyi led the USA at her final Olympic Games tonight.

Although the USA had already sewn up team gold by the time Biles saluted the floor exercise judges during her final routine, winning is not enough for Karolyi and never has been. For 90 seconds, the long-time national team coordinator leaned one way and then another, following Biles' every move. Only after Biles' score was posted did the architect of an American dynasty relax.

Then, something else happened. Something she never saw coming. Karolyi started crying. And not just a little.

"I pride normally being very tough," she said. "I was 'Oh, what's happening to me? What is this?'"

It's goodbye.

Three Americans top the standings in preliminaries

The 73-year-old is stepping away from the program she has spent the last 15 years turning into one of the most dominant forces at the Olympic Games. Her athletes — all of whom she's nurtured from prodigies to champions — repaid her hard work with a fitting tribute of precision and tenacity.

Twenty-eight times in two days they stepped up to compete. And 28 times they hit. No falls. No major wobbles. Nothing but brilliance.

The group — Biles, Raisman, Douglas, Kocian and Hernandez — dubbed themselves 'The Final Five' as a nod to Karolyi.

"It's perfect," Biles said. "It's Martha's last year. We wanted it to be meaningful."

The Rio 2016 Olympic champions admire the fruits of their labour (Photo: Getty Images/Laurence Griffiths)