Despite the knocks, synchronised swimmers steal the show in Rio

The combat zone lurking beneath the water went unnoticed amid a flurry of makeup and flashy bathing suits as Russia's synchronised swimmers got their title defence off the mark on Thursday.

After Natalia Ishchenko and Svetlana Romashina retained the duet title this week, Russia's eight-woman team gave a display of military-style precision to stay on course to maintain their stranglehold on a sport in which they have won every edition since Sydney 2000.

As traditional Olympic sporting favourites such as athletics are struggling to draw the crowds in Rio it was a near capacity crowd following the drama under the blazing sun at the outdoor Maria Lenk Aquatics Centre.

Nose plugs in place, competitors marched out to a backdrop of blasting music, diving in for a three-minute technical routine, as oddly-named elements 'Porpoise twist walkout' and the 'Barracuda Airborne Split' flashed up to help the less knowledgeable among the roaring crowd follow the action under and over the water.

After the first technical routine round favourites Russia had opened up a 1.3932-point lead on rivals China with Japan 3.2383 off the leaders followed by Ukraine, Italy, Brazil, Egypt and Australia.

"Brazil has prepared us for everything -- in cold and in heat, in murky water, in dirty water, in clean water, with wind or with sun," said Russia's Aleksandra Patskevich.

Australia's Danielle Kettlewell was in awe of the technical ability of their rivals.

"Russia are really amazing in this sport, they've mastered synchronised swimming in all aspects. We're really honoured to be competing against them," said the 23-year-old.

It might all seem light hearted but the athleticism required for a sport that combines swimming, dance and gymnastics -- while holding your breath underwater - is unforgiving, says Australia's Bianca Hammett.

"Anyone who makes fun of us should come and give it a go. We train six hours a day."

"Synchronised doesn't really get in the spotlight only once every four years," said Kettlewell. "There's always people out there who will judge it. Say nasty things about it.

"They should try and go upside down and count to eight, holding their breath and be in time with the music and the rest of the team."

Australia were honouring "female warriors" on Thursday and despite sitting last are confident for Friday's second round where they will pay tribute to some of their most famous animals -- the crocodile, Emu, snakes and spiders.

-- Smile despite the concussion --

The darker side of the sport has been the concussion which some competitors have suffered as they clash under the water with throws and lifts increasing the danger.

"Technically it's very complicated, there can be a few bruises, the lifts are quite complicated, and there can be some head knocks here and there," said Australia's Emily Rogers.

China, meanwhile, are perfecting their smile.

The Chinese chose Brazilian music to get the crowd going, as they bid to turn their silver from London 2012 to gold.

"Chinese girls or even girls from East Asia are less outgoing. When we smile, we just simply smile. We don't show our teeth and you can see that our personality is more reserved," said Sun Wenyan, who won duet silver with Huang Xuechen.

"In a sport like artistic gymnastics or synchronised swimming, we need to be graceful and powerful at the same time so it's hard to manage both.

"Our coach told us that we have to find this balance and we tried really hard to do this."