
Carlin Isles' scorching pace meant the American was dubbed "the fastest man in rugby" soon after taking up the sevens format of the game.

Isles' charisma and explosive on-field performances quickly made him a popular figure in a sport that is growing quickly in the U.S.

His try-scoring prowess has helped the U.S. finish sixth in the past two Sevens World Series, beating some of the game's best teams.

Despite the emergence of South African speedster Seabelo Senatla (right), Isles is confident he is still rugby's fastest man.

He is dreaming of qualifying for the Rio 2016 Olympics in sprinting as well as being part of the USA Sevens team.

Isles hopes his rugby training will help him break the 10-second barrier needed to qualify for the U.S. track and field team.

However, USA Sevens coach Mike Friday insists Isles will have to choose between rugby and running.

Perry Baker (right) is another of USA Sevens' speedy secret weapons. Friday likens the double act of Baker and Isles to "The Chuckle Brothers" -- a reference to the British comedy duo.

Friday says Isles (right) is a "born fighter" -- having overcome a traumatic childhood.

Isles told CNN his early years were "about surviving ... it was very difficult."