On the list of "safe" coaching jobs, Texas Tech defensive coordinator is at or near the bottom.
The revolving door that is that position on the Red Raiders' staff continued to swing on Thursday as CoachingSearch.com first reported that Matt Wallerstedt was dismissed from the staff. A school release later in the day said the coach resigned his duties due to personal reasons.
"I have submitted my resignation to Coach Kingsbury effective immediately because I want the best for the Red Raider program, and this will allow them to go in a different direction on defense," Wallerstedt said. "I love our players and this school and have only their best interest in my heart and mind. I wish Coach Kingsbury every success this season."
Assistant Mike Smith will take over duties as defensive coordinator.
Letting Wallerstedt go so early in the season comes as a bit of a surprise, but it's not like Texas Tech was sound on that side of the ball. The team gave up 438 rushing yards in a loss to Arkansas last week to drop to 127th in the country in rushing defense and has allowed 36.7 points per game through the first three weeks of the season.
In other words, stats that can prompt a head coach to make a change. However, the decision might not have been a hard one for Kingsbury to make as a report from ESPN said that Wallerstedt was under the influence of an unknown substance while on campus and sent home on Monday.
Continuity has been a struggle in Lubbock, where the school has had four head coaches in a five-year span and is going on its seventh defensive coordinator in as many seasons.
Wallerstedt joined current head coach Kliff Kingsbury in coming over from Texas A&M prior to the 2012 season. He previously served as defensive coordinator at Air Force and was a linebackers coach at Kansas State, his alma mater.
Smith, the new coordinator, played at the school in the early 2000's and is a Lubbock native, so he knows his way around the program. Although he's young, Smith has a solid NFL background after being drafted in 2005 by the Baltimore Ravens. He later served as linebackers coach for the New York Jets under Rex Ryan, as well.
Smith clearly has his work cut out for him, as Texas Tech has a difficult Big 12 schedule ahead. The Red Raiders are on bye this week and will then travel to Oklahoma State for a Thursday-night game on Sept. 25 to begin conference play.
You can follow Bryan Fischer on Twitter at @BryanDFischer.