Over the course of five years, Brad Stevens has helped transform the Boston Celtics from a lottery team to a title contender.

Stevens' rise, along with the Celtics, has been stunning. He began his career as a volunteer at Butler University, became an assistant coach, then head coach, and teams from around the world tried to poach with him million-dollar offers.

Stevens eventually took an offer from the Celtics. He has installed a motion offense and stingy defense that's helped make them one of the best teams in the NBA.

The NBA world has taken notice, as a former college assistant is beating NBA coaches at a level nobody expected.

Here's how Stevens has risen from an assistant making $18,000 a year collecting film to one of the best coaches in the pros.