Reports: Texas Tech fires defensive coordinator Matt Wallerstedt (Update)

Update: September 14, 2:00 p.m. ET

ESPN.com's Jake Trotter is reporting that Wallerstedt was fired after he was "suspected of being at the school's football building while under the influence of a controlled substance." Citing a source, Trotter's report says that Wallerstedt was "sent home from the facility Monday."

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Less than a week after giving up 438 rushing yards in a 49-28 home loss to Arkansas, Texas Tech has reportedly fired defensive coordinator Matt Wallerstedt from its staff.

Chris Level of RedRaiderSports.com is reporting that co-defensive coordinator and outside linebackers coach Mike Smith will take over the reigns of the defense.

Wallerstedt was in his second season with the Red Raiders under head coach Kliff Kingsbury after being hired in January 2013. He previously had stints coaching at Texas A&M, Air Force, Kansas State and Akron, among others. Through three games in 2014, the 2-1 Red Raiders had the nation’s 94th ranked defense and the 124th ranked rushing defense (out of 125 teams).

Despite the team's defensive struggles, RedRaiderSports.com's Matt Clare is reporting that Wallerstedt's dismissal is "not due to on-field performance."

Smith, a TTU alum who played two seasons in the NFL, will now be the seventh Texas Tech defensive coordinator in the last eight seasons. Smith returned to his alma mater in 2013 after serving as an assistant with the New York Jets and at the University of Hawaii.

Texas Tech has a bye this week. Its next game is on the road against Oklahoma State on September 25.

The news was first reported by Pete Roussel of CoachingSearch.com.

For more Texas Tech news, visit RedRaiderSports.com.

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