Swimmer Tamara Potocka has collapsed following the women’s 200-metre individual medley.
The Slovakian athlete, 21, was carried away from the pool on a stretcher.
A Slovakian team official told the PA news agency Potocka had an asthma attack after her race.
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She was then seen with an oxygen mask as she was taken away for further examination. She was taken to hospital for further monitoring.
Potocka had finished seventh in the third heat of the event in the morning session at La Defense Arena in Nanterre, Paris.
She then collapsed after she got out of the water and was immediately surrounded by a group of medical attendants.
The venue’s media manager confirmed to news agency Reuters that she was conscious.
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Paris 2024 marks Potocka’s Olympic debut.
Her time of two minutes 14.20 seconds was not fast enough to advance her to the semi-finals of the event, eliminating her from the competition.
Potocka was a four-time finalist at the 2024 European Championships.