2015 FINA World Championships: Australia women’s relay takes gold

Finally, Australian coach Jacco Verhaeren can smile after the women's 4x100m freestyle relay team claimed a stunning gold at the world swimming championships in Russia.

Australia's Emily Seebohm, Emma McKeon and sisters Bronte and Cate Campbell clocked a meet record three minutes, 31.48 seconds on Sunday night to turn around what loomed as a disastrous first day in Kazan.

Jess Ashwood opened the team medal tally with 400m freestyle bronze.

Verhaeren appeared livid over the Australian men's horror start to the eight-day meet.

World champion Christian Sprenger (100m breaststroke), world No.1 Mack Horton (400m freestyle), and the fancied men's 4x100m freestyle relay team failed to qualify for their respective finals.

"It's a world championships and you don't get away with an easy swim ... you have to step up," Verhaeren said of the men's shocker.

However, he was all smiles after Bronte Campbell's sizzling 51.77 third leg set up her sister and world 100m champ Cate to comfortably bring home the women's relay win.

Australia - the world record holders with 3:30.98 - avenged their 2013 world titles silver finish behind the US.

"To come second (in 2013) was amazing, but to stand together on the podium and sing the national anthem with your big sister is something not many get to do. It's my highlight of the year," Bronte Campbell said.

The Netherlands (3:33.67) took silver and defending champions the US bronze (3:34.61).

Ashwood, 22, claimed 400m bronze (4:03.34 PB) behind American defending champion and world record holder Katie Ledecky (3:59.13, meet record).

Ashwood, who suffers from severe scoliosis or curvature of the spine, won Australia's first 400m freestyle world championship medal since Hayley Lewis in Perth in 1991.

Meanwhile, McKeon (6th; 57.59) made Monday's women's 100m butterfly final, unlike compatriot Madeline Groves (11th; 58.17).

But the one to beat is Swede Sarah Sjostrom (55.74), who set a new world record in Sunday's semis, eclipsing American Dana Vollmer's 2012 mark (55.98).

Tessa Wallace (16th; 2:14.34) missed the women's 200m IM final.

China's Olympic champion Sun Yang defended his 400m freestyle world title in a final without Horton in a shock start by the men.

Australia's 4x100m relay team sorely missed rested Pan Pacs champion Cameron McEvoy and absent world champion James Magnussen (shoulder) to also fail to make the medal race, finishing 13th (3:16.34) in the heats.

Teenager Kyle Chalmers was a shining light with his superb second leg (47.92) for Australia, who were fourth at the London Games and 2013 worlds.

World and Olympic champions France (3:10.74) later won 4x100m relay gold.

Jake Packard (7th; 59.66) made the men's 100m breaststroke final in Sprenger's absence.

In Monday, heats action are world No.1 Seebohm (women's 100m backstroke), medal hopes McEvoy (men's 200m freestyle) and Mitch Larkin (men's 100m backstroke) plus Taylor McKeown (women's 100m breaststroke) and Ashwood (1500m freestyle)

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