Shakes-Drayton ran a lifetime best in slippery conditions to destroy a world-class field to win the 400m hurdles at the Aviva London Grand Prix.
Her time of 53.77 is the second fastest British performance of all time, leaving European champion Irina Davydova was left trailing in her wake, with Jamaica's Kaliese Spencer third and reigning Olympic champion Melaine Walker more than 1.7 seconds back in fourth.
Ranked 21st in the world before the race, Shakes-Drayton will now be considered a serious medal contender in London's Olympic Stadium, but she insists the hard work is not over.
"I'm over the moon with the time," she said. "I thought it was an opportunity to race the best girls which I haven't had this year. I thought 'Come on girl, pull your socks up, you have to go for it', and I sure went for it. I just believed in myself and reminded myself what I've done. I've had a good day at the office.
"It gives me confidence knowing that my training is going well but I'm not going to let it get to me too much. I'm still going to remain level-headed because it's not finished yet."
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