Polish gymnast Joanna Skowronska has been diagnosed with a broken cervical vertebra in her neck following a fall while training on Thursday. Olympic gymnastics officials said the 22-year-old, who was practising on the asymmetric bars, was in a stable condition in an Athens hospital.
She will have to wear a supporting brace for the next eight weeks.
Argentina's Celeste Carnevale, the first reserve gymnast, is expected to take Skowronska's place.