Welwyn Garden City's Jodie Williams came through her heat of the 400m in style - the win taking her into the semi-final.
The 27-year-old ran 50.99 seconds to rank seventh in the qualifiers for Wednesday's next stage.
She said: "It felt great, like I didn’t really put a huge amount into any of it really and I felt really smooth in that first 300m and I just tried to put myself in a really good position coming off the top bend.
"I wanted to take the win because I know how important the semi-finals are so yes I am happy with it.
"I executed my plan, I stayed nice and smooth, didn’t put too much into the first 300m really and got myself into a really good position to come home. I’m happy with it."
But she knows that this is just one step on her journey.
She said: "I’ll have to put a lot into that semi to make the final obviously but I’ve been practicing all year for this."
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