Dina Asher-Smith was beaten into second place in her heat for the 100 metres at Tokyo 2020.
The Briton, the world champion over 200m, arrived in Japan tipped to challenge for a medal in the two sprint events.
She arrived on the back of a season’s best of 10.91 and it looked good as she flew out of the blocks and opened up a lead over her rivals.
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However, she was unable to extend the advantage and was hunted down by Teahna Daniels.
Asher-Smith did not look overly alarmed as the American drew alongside, with energy conservation clearly of major importance, but it was surprising to see her run down late in the race.
Still, it was enough to take her into the semi-finals in a time of 11.07. The semi-finals and final take place on Saturday.
Shelly-Ann Fraser-Pryce arrived in Tokyo as the favourite for 100m glory, having run a staggering personal best of 10.63 earlier in the year.
The 34-year-old blasted out of the blocks and sauntered to victory in her heat in a time of 10.84.
Team GB’s Daryll Neita claimed second place in Heat 4 behind world number three Marie-Josee Ta Lou to advance to the semis.
Ta Lou produced a blistering run, with her time of 10.78 a new African record - while Neita stopped the clock in a personal best of 10.96.
Asha Philip made it a good day for Team GB sprinters as she took second place behind Blessing Okagbare to progress to the semi-finals.
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