South African swimmer Achmat Hassiem said the shark which attacked him has given him a chance to "change the world".
Achmat Hassiem will visualise the shark which bit off half of his right leg and enabled him to become "a hero to the world" when he eyes more Paralympic glory in Rio.
South African Hassiem was taking part in a lifeguard training exercise off Muizenberg beach, near Cape Town a decade ago when he saw a shark, which he has named Scarlet, circling his younger brother.
Hassiem tried to distract the predator by slapping his hand on the water, but came under attack himself and the shark sunk its teeth into his right leg.
Rather than being bitter about losing his leg below the knee, the 34-year-old - nicknamed 'Shark Boy' - has taken a role trying to protect sharks and is grateful to the giant fish for the opportunities it has presented him with.
He said: "I was recently made a global marine guardian by the UN. My forte is sharks - who better to protect them than me?
"The shark has given me so many opportunities, opportunities to represent my country, to change the world. It took me from being a little kid with dreams to actually being a little kid who has achieved all those dreams.
"I have become a shark advocate because it is my way of thanking her for giving me everything I have achieved today and it is my way of thinking I am a hero to the world, hence the nickname 'Shark Boy'."
Hassiem won bronze in 100 metre butterfly S10 at the 2012 Games in London and will think back to the life-changing day in 2006 when he goes for more medals in the S10 100m freestyle and 100m butterfly at his final Paralympics.
"I think about that moment when the shark is coming, that knock on your leg, when your senses switch on, everything activates and I see this massive fin comes out of the water," he said.
"Believe me, when I am in the water I am flying."
The opening ceremony for the Games will be staged at the Maracana Stadium on Wednesday.