Bridgend's Marc Jenkins has been called into Britain's triathlon team in place of the injured Paul Amey. "To be able to call on Marc is a fortunate situation for the squad," said triathlon team leader Graeme Maw.
"He is a proven international competitor and the current national champion and will join the other team members in Cyprus this week."
Amey was ruled out after fracturing his pelvis in a bicycle crash in Italy earlier this week.
"We are devastated for Paul as he has committed four years' hard work to these Games after missing out on Sydney with a stress fracture to his shin," said Maw.
"He has demonstrated his extraordinary talent in qualifying for the Games and it will be a great shame that his talent will not be on show in Athens."
Jenkins, 28, was disappointed to miss out on selection for the original party after finishing 14th at the World Championships in Madeira in May.