Keely Hodgkinson pulled out off the 400m final at the UK Athletics Championships as a precaution, Sky Sports News understands.
The 800m Olympic champion has been competing over the short distance in a bid to improve her first-lap speed and challenge the 800m record later this summer, after breaking the indoor world record with a time of 1:54.87 in France earlier this year.
Hodgkinson, 24, qualified from the heats on Saturday but pulled out from the final moments before it was due to start. She looked emotional as she stood at the side of the track in Birmingham.
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Sky Sports News has been told by her coach Trevor Painter that "all is fine, bit of tightness and decided not to risk it".
It is understood that Hodgkinson felt anxious during the warm-up and on the start-line before deciding to withdraw and avoid long-term injury, after suffering from several hamstring injuries last year.
The move is understood to be precautionary, given her main aim of the season is to win the 800m race at the European Championships and to try an break the record in London on July 18.
Hodgkinson said: "I wasn't feeling 100 per cent standing on the start-line, so I made the tough decision to step away and not race.
"I didn't want to risk anything this summer."
The 800m world record of 1:53.28 was set by Czech Jarmila Kratochvilova 43 years ago.
(c) Sky Sports 2026: Keely Hodgkinson: Olympic gold medalist pulls out of UK Athletics Championships 400m final as precaution
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