Former Detroit Lions running back Jahvid Best will compete at the Rio Olympics as a member of the St Lucia Olympic track team.
Best was a first-round pick for the Lions in the 2010 NFL Draft, but his career ended after just three seasons after a series of concussions.
However, the 27-year-old was a standout sprinter in high school and is to return to his track and field roots to represent St Lucia in the 100 metres in Brazil.
"When I think of the road I have travelled to get here I get tons of emotions," he told NBC Sports.
"A couple of years ago my lifetime dream was crushed. I was devastated, but I never stopped dreaming and believing in myself.
"My family has instilled a lot of values that has enabled me to persevere through it all.
"This is a huge accomplishment for me, but at the same time this is just the beginning. I have only been in this sport for two years professionally, and plan on being around for a long time."
Best, whose father is from St Lucia and who holds dual citizenship, posted a personal best time of 10.16 seconds in April, but that would not have been enough to get him into the finals of the United States Olympic Trials earlier this month.
Best will be the first athlete with prior NFL experience to compete in the Summer Olympics.