Sayers, 25, from Newmarket, is ranked in the top six in the world and is set to compete at her second Olympics.
She says she perfected her throwing technique as a child, taking on my brother at throwing cooking apples up a fir tree.
"I always had a dream to compete for my country at something and thought it would be in a ball game. I didn't think it would be at the Olympics," she said.
Sayers failed to reach the final four years ago but will expect to get through qualifying on 19 August, and compete two days later in the final, starting at 1220 BST.
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