Cameron Crombie didn't know he had cerebral palsy until he was 22 and even then Paralympic officials couldn't find a classification for his impairment.
But almost a decade after the revelation, the Canberra volunteer firefighter will make his world para athletics debut in London on Saturday morning Australian time.
Crombie has hemiplegia in his left arm and leg after a stroke during premature birth, but the 31-year-old was never told of his condition and grew up playing sport alongside his identical twin brother.
Boasting a 197cm frame, Crombie excelled in sports growing up in Newcastle and played state level basketball, despite lacking the fine-motorskills of his competitors.
"When I was growing up if I could be outside playing sport then I would be, that was just normal and any difficulty I had didn't seem any greater than the next person," Crombie said.
"I guess you only know what you know and I knew no different. A couple of things were a bit strange but I just thought that's how things were for everyone."
Crombie moved to Canberra after university and was shocked to learn of his condition from a relative, but said there was no point getting upset and quickly found his way into para-sports.
"My parents did the best by me bringing me up as close to a normal child as they could and gave me plenty of great opportunities in life," Crombie said.
"But it definitely explained a lot of things with being fatigued and coordination stuff that people with CP suffer with. It wasn't really a negative experience finding out, I just took it on board and thought let's see what I can do now."
Crombie became a national para-rowing champion but complications surrounding his classification put an end to his Rio Paralympics dream.
A collaboration between Rowing Australia and Athletics Australia saw Crombie classified as an F38 in shot put and javelin and began training under six-time Paralympian Hamish McDonald.
"After missing out on rowing it was a bit heartbreaking but it was just a case of move the goalposts and get straight back into training, I just had to move on," Crombie said.
"In hindsight, having come so close a couple of times and getting to the point now where I've earned a spot, it's made it all worthwhile and maybe even more rewarding."
McDonald is a three-time Paralympics shot put champion with cerebral palsy and Crombie said he's "unbelievably lucky" to train 30 hours a week under a legend of the sport.
"Having someone as experienced as him is huge advantage and I wouldn't be here without him. The time and effort he puts into our training, you can see he only wants the best for me," Crombie said.
"But he also cares on a personal level, he cares about my mental state and what's going on outside of sport which is really important."
Crombie holds the shot put Australian record after throwing 14.92m last month and has the 15.58m world record in his sights, while his javelin personal best is 44.33m.
"The hard work has been done and I'll just go out and try and put the pieces together and hope for a good result. If I can throw pbs in both events that'll be a good result for me," Crombie said.
"I've got my family here and it's a pretty special thing getting to represent your country so I'm really looking forward to it."
Crombie is gunning for shot put at the Gold Coast Commonwealth Games next year and javelin at the Tokyo Olympics in 2020, he will compete in the javelin in London next Saturday.