Carlin Isles has come a long way.
The former track and field phenom-turned-U.S. rugby star from Ohio never imagined competing at an Olympic Games.
Isles bounced around foster homes before he was adopted by Charles and Starlett Isles at age 7.
On Tuesday, Isles, 26, competed with the U.S. men's rugby team in its first Olympic matches since 1924.
"I had a picture I wanted to paint for myself and my life," Isles told NBC News. "I wasn't going to let nobody dab their paintbrush in my painting."
Isles began his improbable journey to Rio in June 2012 while he was training for the Olympic trials in track and field. He watched rugby online, and, immediately, he says, he was hooked. The way both teams' fastest players dashed away from tackles to score tries — long runs to the other team's end zone — was mesmerizing to the young American.
Isles got in contact with Nigel Melville, then chief executive of USA Rugby, and asked for a chance to try out for the national team. Melville called him the next morning, Isles says, inviting him to the team's headquarters in Aspen, Colo.
Despite never having played rugby sevens — a sped-up version of rugby union that features teams of seven who play seven-minute halves — Isles leaped at the opportunity, dropping his running spikes for cleats.
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Isles immediately impressed U.S. coaches with his break-neck speed. As a sprinter, Isles ran the 100 meters in 10.15 seconds — not good enough to make the U.S. team, but lightning pace for a rugby player.
Over the last four years, he's used that speed to torment opponents. The man who had never so much as touched a rugby ball four years ago today is widely regarded as the world's fastest player and one of its most exciting prospects.
"This dude is fast. He is lightning fast. Like, right now fast," said teammate Perry Baker.
Isles hopes to lead an upstart U.S. squad to a respectable showing in Rio, perhaps even with an outside shot at a medal.
Isles' speed and rare athletic talent even persuaded a gym owner in Canton, Ohio, to sponsor his private training for Rio. Chris Maggiore bought Isles a car and paid for the training.
"I just really believed in him and thought he could do it," Maggiore said. "And I think I'm a good judge of character."
That character, Isles says, is captured in a tattoo emblazoned across his chest that reads "Focus." It is that trait, he says, that has fueled his rise from orphan to Olympian.
"You have to understand that it doesn't matter where you come from," Isles says. "You don't have to be your circumstances. You can change your picture how you want to change it."