Montgomery attended Burns High School in Lawndale, North Carolina, and was a standout in football, basketball, and track. In football, he was a two-time Team MVP, and as a senior, helped lead his team to the State 3A title. In basketball, he won an All-Conference honors and was named the Team MVP. In track, he won All-Conference honors and was the conference champion on the 200 and the 400 meter dashes.
Montgomery attended Duke University from 1996–99, finishing his career with 171 receptions (ranking second in Duke's history) for 2,379 yards (third), four 100-yard receiving games (seventh), and 13 touchdowns (eighth). He earned the team's MVP award in 1998 and 1999, becoming just one of five two-time team MVPs in Duke history. Montgomery joins Clarkston Hines as the only Duke players to have three straight seasons with more than 50 receptions and 600 yards.
Montgomery entered the National Football League in 2000 as a rookie free agent with the Carolina Panthers. From there, he would play for the Denver Broncos for 3 years (2000–2002) and the Oakland Raiders (2003). In 2005, he would play for the Georgia Force in the Arena Football League.
Montgomery began his coaching career at his alma mater, Duke University, where he served as the wide receivers coach for four seasons (2006–2009).
Montgomery was hired by the Pittsburgh Steelers on February 16, 2010 as the new wide receivers coach, replacing Randy Fichtner, who moved to quarterback coach upon the retirement of Ken Anderson. He remained with the Steeler organization for three seasons. Notable players coached include Mike Wallace (Pro Bowl 2011), Hines Ward, Emmanuel Sanders, Antwaan Randle El, Antonio Brown (Pro Bowl 2011), and Jerricho Cotchery.
Montgomery returned to Duke as associate head coach and offensive coordinator/passing game while coaching the wide receivers, in 2013. Duke promoted him to offensive coordinator in 2014. Montgomery coached Jamison Crowder (2015, 4th round/#105, Washington Redskins) during 2013 and 2014 seasons.
East Carolina University named Montgomery its head coach on December 13, 2015, replacing Ruffin McNeil.