Molly Renshaw is to appeal against her exclusion from Team GB's swimming squad for London 2012.
The 16-year-old did not achieve the required Olympic qualifying time at last week's ASA National Championships.
Renshaw won the 200 metres breastroke but her time of two minutes 27.72 seconds was 0.83 seconds outside the FINA 'A' qualifying standard time.
A team representing the swimmer have announced they are appealing against the decision.
They are arguing that British Swimming is being unreasonable in its selection policy.
Renshaw, who made an impression on last year's World Championships as a 15-year-old, had swam the qualifying time before, recording 2:26.81 to finish second to Stacey Tadd at the first trial in March.
However, the rules state that only the race winner was guaranteed a place on the squad.
Last Friday, Renshaw's coach Andi Manley told BBC Radio Derby that an "over-complicated selection process" was to blame for the Derbyshire teenager failing to be selected for the Olympics.