Aussie women fall just short of relay gold

The women's relay team of Shayna Jack, Bronte Campbell, Brittany Elmslie and Emma McKeon finished second in the 4x100m freestyle to pick up Australia's second medal of the world championships.

Emma McKeon touched the wall three tenths of a second behind American Simone Manuel in an epic finish.

McKeon had been quick in her 100m butterfly event but was proud to have come so close with the 18-year-old Jack competing in place of Olympic champion Cate Campbell.

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"I was mostly excited tonight for this race, to be back in the relay with these girls," McKeon told Channel 7.

"It's always such a fun time. We're very happy with second place."

Bronte Campbell swam a 52.14, the fastest second leg of the race, despite battling shoulder problems at the championships.

"It probably (hurt) a lot but it was all I had to give tonight," Campbell said.

"I'm really proud of how everyone swam. Second place is nothing to be sneezed at and I think we all did a really good job."

Jack conceded she was "so nervous" in the starting room before she was lifted by her teammates ahead of the race.