BRAINTREE — Billy Traft had unfinished business. In 2007, he had pretty well retired from amateur boxing and was focusing on his career as a Boston police officer.

He was enjoying his evenings coaching kids at TNT gym and was helping his cousin, Billy, prepare for the Golden Gloves. Because his cousin lacked sparring partners, Traft became one of them. That’s when he decided to get back into the ring in competitive fashion.