Welshman Joe Thomas's dream of running in the 800m at the 2012 London Olympics has been ended by a stress fracture to his shin.
The 24-year-old from Pontypridd won the UK indoor title in February.
But he tweeted: "No Olympics or track season for me this year. A few lengthy battles with niggles has resulted in a stress fracture."
Thomas set a Welsh 800m indoor record of 1:46:33 at a race in Stockholm, Sweden in February.