Miller was born on February 20, 1979, in
Utah, and grew up in
Hesperia, California. Both of his parents were schoolteachers, and his father served as the wrestling coach at
Serrano High School, where Miller began wrestling competitively. Miller qualified for the California state wrestling championships as a junior and finished eighth in the state during his senior year. After graduating high school, Miller attended
Brigham Young University and wrestled there for one year. However, his collegiate wrestling career was cut short when his father was severely injured in a car accident, leaving him bedridden. Miller returned to California to assist with coaching his father's high school wrestling team. During this time, Miller was introduced to mixed martial arts through his friendship with a young
Joe Stevenson, who was already competing professionally. Stevenson invited Miller to train at Williams Combat Grappling, a gym run by UFC veteran and King of the Cage founder
Tedd Williams. There, Miller trained alongside future MMA professionals Stevenson and
Jason Lambert, eventually transitioning into professional mixed martial arts himself. ==Mixed martial arts career==