Arnett attended La Cueva High School in Albuquerque, New Mexico and was a two-sport athlete in football and baseball.[1][2] He originally accepted an offer to play for the New Mexico Lobos baseball team, but he earned a scholarship to the football team in the summer of 2005. He excelled on the field and in the classroom during his college career, earning six forced fumbles and was a first-team Academic All-American in 2008.[3]
Coaching career
San Diego State
After being away from football for two years, he became a graduate assistant at San Diego State under his New Mexico head coach Rocky Long. Within three years, he was promoted to linebackers coach. His linebacker unit produced five different All-Mountain West selections, including 3-time All-Mountain West selection Calvin Munson.[4] In 2018, he was promoted again, this time to defensive coordinator. Under him, San Diego State ranked 32nd in total defense in 2018 and 2nd in 2019, which was a 30-place gain from the year before.[5][6]
Mississippi State
On January 11, 2020, Arnett was named the new defensive coordinator at Syracuse. However, the stint with Syracuse was short-lived, as he was hired as the defensive coordinator and linebackers coach by Mississippi State on January 22, 2020.[7]
Arnett was named interim head coach at Mississippi State after Mike Leach was hospitalized on December 11, 2022.[8][9] After Leach's death, Mississippi State removed the interim tag from Arnett's title and named him the 35th full-time head coach in school history on December 15, 2022.[10] Mississippi State fired Arnett on November 13, 2023, with two games left in the regular season.[11]