Sarah Sjöström's time of 25.43 was one second slower than her own world record.

The fastest was the Chinese Yufei Zhang, four hundredths ahead of the Swede.

It will be an intense final session for Sjöström tonight when she first swims the final in the 100 meters freestyle at 18.02 and then the semifinal in the 50 butterfly just over an hour later.

- I do my best and we'll see where it's enough.

I may just need a few more races.

We will see if it fits better in the semifinals and the final, says Sjöström.

Sara Junevik also made it to the semifinals in the time of 25.94, one tenth of her personal best.

She finished third in her heat.

- It was great to have a good race.

I'm pleasantly surprised, so it's really nice, she says.

CLIP: Sara Junevik advanced to the semifinals of the 50 meter butterfly

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Sara Junevik advanced to the semifinals of the 50 meter butterfly