One-handed boxer defies sports authorities to win first pro fight

American boxer Michael Costantino has just won his first professional fight despite an incredible handicap: he only has one hand.

The 33-year-old New Yorker had to battle sports authorities even to be allowed into the ring against Nathan Ortiz at the Aviator Arena in Brooklyn at the weekend.

But the cruiserweight fighter justified his perseverance by earning a second round knockout victory in front of an estimated 1,500 fans.