'Grandma' Raisman stands between Biles and all-around Rio gold

Aly Raisman will be bidding to put her heartbreak from the London Games behind her as she bids to spoil US teammate Simone Biles' race for a record haul of five golds in Rio in the Olympic women's all-around event.

Biles is overwhelming favourite after snapping up every individual title on offer in the last three years.

The 19-year-old is the reigning three-time all-around champion and a holder of a record ten world titles.

Both fought side by side to lift the United States to a third Olympic team title on Tuesday to keep Biles' bid for an unprecedented five golds in Rio on track.

But on Thursday night in the Rio Olympic Arena they will be fighting alone.

Texan Biles is expected to add the all-around to her first Olympic title -- team gold -- and follow with gold on the vault, balance beam and floor exercise next week.

But Bostonian Raisman, known as the 'Grandma' of the team at 22 years, has experience on her side in her second Olympics.

The US team are so strong because they are very competitive among themselves, she said.

"We make it look easy but it's a lot of hard work. Every day in the gym Martha (Karolyi) makes us feel like it's a competition," said Raisman.

Team coordinator Martha Karolyi is expecting two all-around medals.

"At this moment, I can say the United States dominates the world of gymnastics," said Karolyi.

Raisman missed the podium in London after ending up tied for third place with Russia's Aliya Mustafina.

She had expected both would receive bronze after finishing behind Gabby Douglas of the United States and Victoria Komova of Russia.

But Mustafina took bronze thanks to gymnastics' bizarre and complicated tiebreaker system.

But with four Olympic medals -- three in gold -- she has the advantage of knowing what it is like to compete individually in a Games.

And despite a disappointing worlds in October the reigning Olympic floor champion was the only gymnast to hit all her routines at the US championships and trials.

- Beyonce-inspired -

Douglas, 20, failed to make the cut to defend her title despite finishing third in qualifiers behind Biles and Raisman. Only two competitors can compete per nation in the final.

Raisman finished 1.759 behind Biles with Brazil's Rebeca Andrade a further two points back in qualifiers with the USA bidding for a one-two finish for the second time in after 2008.

But Biles is taking the overwhelming expectation in her stride too.

"There's no biggest challenge. The hardest challenge (now) is getting to sleep because we are so excited, going back to training and to keep pushing," she said.

"Of course you are nervous, but we just did exactly what we did in training.

"Martha always says just do whatever you're doing in training, don't do anything more and don't do anything less.

"We've been with her for a couple of weeks now doing competition routines every single day in the gym. There's really no secret, just a lot of hard work."

Andrade, 17, will be hoping to put the hosts on the podium for the first time.

She is one of the few gymnasts who hit the Amanar ?- the big vault that only Biles and a few other women can do ?- and gives an entertaining Beyonce-inspired floor routine, which was a medley of "Crazy in Love" and "Single Ladies", including choreography from the iconic music video.

Russians Mustafina and Seda Tutkhalian are targeting the podium after taking team silver, along with China's Wang Yan and Shang Chunsong, team bronze medallists.