Para-swimmer Tully Kearney is out of the ParalympicsGB squad due to injury.
Four-time world champion Kearney has been managing an injury throughout 2016, but has not fully recovered and as a result has chosen to withdraw.
The 19-year-old from Aldridge has a condition which causes muscle weakness.
"I'm devastated not to be able to represent GB at the Paralympic Games in Rio. I have worked incredibly hard in training for many years to get to this point," said Kearney.
"I have been battling a recent progression in my condition and this, coupled with ongoing shoulder injury over the past six months, has massively affected my ability to train."
Kearney, who made the top three in last year's BBC Young Sports Personality of the Year Award, will not be replaced in the ParalympicsGB swimming team for the Games, which begin on 7 September.
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