In July 2007, while serving with the British Army in Afghanistan, his vehicle hit an improvised device. He lost both of his legs in the explosion and was pronounced dead in hospital at Camp Bastian. But one of the doctors found a pulse and his long road to recovery started.
Since then, Derenalagi has been heavily associated with Battle Back, first getting involved with Paralympic sport when he took part in a training camp in the United States in 2009 and realising he had a talent for the shot, discus and javelin. He concentrated initially on the shot but since last October has focused on the discus, which is the event he will compete in in London.
The 37-year-old former rugby player says he would have become “a miserable person without sport” and warmed up for the Games with victory in the European Championships in the Netherlands in June. A medal in London on the opening day of athletics action on 31 August is well within his capabilities.
HE SAYS: “I know I was born in Fiji but I was so proud and honoured to represent Britain in the front line in Afghanistan and now it is an honour to represent Britain in a different arena in the Paralympics – it is the biggest achievement I have done in my life.
“I’m so excited to have the chance to compete in front of a home crowd and a massive television audience and being on the podium is my main target.
“Sport has been the best rehab possible for me. It doesn’t only help me physically but also mentally in taking away a lot of the negative thoughts from having such a horrific injury. It has allowed me to stay focused and keep working hard and get fit. People say I am a machine but I am not a machine, I am a person and I love what I do.
“The most important thing I have learned since the accident is to accept whatever obstacles you go through in life, because nothing can change that, but you can change tomorrow.”