Brown started his coaching career as a graduate assistant at UMass. Before joining Larry Blakeney's staff at Troy to work under Tony Franklin, he spent one-year assistant coaching stints at UMass, Sacred Heart, and Delaware. Following Franklin's departure to Auburn at the end of the 2007 regular season, Brown was promoted to offensive coordinator at Troy. When he was hired, he became the youngest coordinator in all FBS football.
On January 12, 2010, Brown was announced as the offensive coordinator at Texas Tech under new Red Raiders head coach Tommy Tuberville. During the 2010 football season, the Red Raider offense performed well. During his tenure at Texas Tech, Brown perfected his NASCAR spread offense. The offense created by Brown focused on players running to the line immediately after the play and quickly snapping the ball before the defense could get set. The offense requires speed at every position to be run the way Brown envisions it. The focus of the offense was to snap the ball 8 seconds after the previous play. The 2010 Red Raiders ranked 15th in the country in total offense, 6th in passing offense, and 72nd in rushing offense. For his coaching performance during the 2011 41–38 upset victory over the then-ranked #3 Oklahoma Sooners, he was recognized by Rivals.com as National Coordinator of the Week. Brown was considered for the head coaching job at his alma mater, UMass, following the 2011 season. Brown was also considered for the school's head coaching job when it opened following the 2008 season.
Kentucky
On December 9, 2012 it was reported after several weeks of speculation that Brown would return to his home state to coach the offense at Kentucky under new coach Mark Stoops.
Troy
Troy announced Brown's hire on Sunday, November 30, 2014. In 2015, Brown's Trojans posted a 4–8 record. Troy was ranked for the first time in the AP top 25 on November 13, 2016, they became the first team from the Sun Belt Conference to be ranked in the Top 25 and finished the year with a record of 10–3. This was Troy's first 10 win season since joining FBS in 2001. Troy capped of the 2016 season by winning the Dollar General Bowl in Mobile, Alabama. In Brown's third season at the helm in 2017, he led Troy to a 3–1 start to begin the season. In the fifth game of the season on September 30, Troy faced #25-ranked LSU. With Troy leading in the third quarter by a score of 24–7, LSU began to mount a comeback in the fourth quarter by scoring 14 unanswered points and trailing just 24–21 with less than 30 seconds left in the game. LSU began to move the ball down-field before having only 8 seconds left on the clock. The very next play became an interception for Troy, which sealed the upset victory. The win over LSU snapped the Tigers' 46-game non-conference home winning streak, which was the longest such streak in the country at the time. The Trojans became Sun Belt co-champions after defeating Arkansas State in a thriller, 32–25. Troy's 10–2 overall record is the programs best regular season finish since joining the FBS in 2001.
West Virginia
Brown was announced as the 35th head football coach for West Virginia University on January 5, 2019.
Personal life
Brown is a member of the Boyle County Baseball and Football Hall of Fame. He is married to Brooke Brown, and the couple have two daughters, Adalyn and Anslee, and a son, Dax. He is also a committed Christian and has worked with the Fellowship of Christian Athletes throughout his career. During a speech at the 2016 FCA Athletes of the year awards banquet, Brown was quoted saying, “Your life is your testimony. Who you are, what you’re about, how you live is your testimony.” Additionally quoted from the same speech, “Your principles must stay the same in the high times and low times,” he said. “Consistency creates trust.”