In a no surprise hire, Cassity announced as Oklahoma State’s new Defensive Coordinator
STILLWATER, Okla. —
Oklahoma State football coach Eric Morris named the first member of his coaching staff on December 12, 2025, appointing Skyler Cassity as defensive coordinator. Cassity, who served in the same role under Morris at North Texas in 2025, will join the Cowboys following UNT’s appearance in the Isleta New Mexico Bowl.
At just 31 years old, Cassity brings four years of experience as an NCAA Division I defensive coordinator, having led defenses at Abilene Christian (2022-23), Sam Houston (2024), and North Texas (2025). His rapid rise through the ranks began after a career-ending injury at Auburn, where he earned a business administration degree in 2016. He started as a student assistant for the Tigers from 2014-16, contributing to an SEC powerhouse. He then served as a graduate assistant at Texas State (2016) and Texas Tech (2017-19), focusing on defensive line and outside linebackers while earning a master’s in sports management.
Cassity’s first full-time role came at Missouri State (2020-21) under Bobby Petrino, coaching outside linebackers, nickels, and safeties. There, the Bears made back-to-back FCS Playoffs, snapping a 30-year drought. As a coordinator at Abilene Christian, he led the Wildcats to 12 wins, the most since their Division I transition. In 2022, his defense topped the Western Athletic Conference in rushing, scoring, and total defense, ranking in the FCS top 20 for rushing yards allowed, with strong metrics in third-down and first-down defense. They finished 7-4 overall. In 2023, ACU ranked second in the United Athletic Conference, 23rd in FCS interceptions (12), 29th in defensive touchdowns, and 27th in fourth-down stops. His units held 14 of 19 FCS opponents under their scoring averages and produced four all-conference players.
In 2024 at Sam Houston, Cassity orchestrated a remarkable turnaround, elevating a 3-9 squad to 10-3 and a New Orleans Bowl victory (31-26 over Georgia Southern). The Bearkats’ defense ranked 22nd in FBS total defense, 13th in pass defense, and seventh in turnovers forced (27). They allowed 21.0 points per game, improving from 64th to 21st in scoring defense, 88th to 22nd in total yards, 92nd to 57th in rushing, and 77th to 13th in passing. In Conference USA, they led in scoring defense and interceptions, holding eight opponents below averages and nine to 21 points or fewer, including a stingy 15.3 points in the final six games.
Reuniting with Morris at North Texas in 2025, Cassity’s 4-2-5 scheme transformed the Mean Green, cutting points allowed from 34.1 in 2024 to 24.9, and yards from 460.5 to 370.2. They forced 25 turnovers (15th nationally), with pass defense at 19th in FBS, improving 51-59 spots in key rankings and excelling in conference play. Entering bowl season, his UNT defense ranked among the top 25 in the FBS in fumbles recovered (No. 3), turnovers gained (No. 6), passing yards allowed (No. 10), passes intercepted (No. 20), and passing efficiency defense (No. 21).
Cassity has deep ties to Oklahoma State: His brother, Braden, played football at OSU from 2018-23; his father, Mike, served as co-defensive coordinator during a long college coaching career; and his mother, Colleen Hartman Rambusch, worked for OSU athletics in radio and TV during the Bob Simmons and Eddie Sutton eras.
Recognized on 247Sports’ “30 Under 30” (2023) and AFCA’s “35 Under 35” (2024), Cassity is known for implementing a multiple, personnel-adaptive defense that prioritizes aggression and opportunism. This could address the Cowboys’ recent defensive struggles, where they allowed over 30 points per game in 2024-25. With Morris’ offensive prowess, this pairing might propel Oklahoma State back into Big 12 contention, fostering a culture of toughness and turnover creation. All university hires are pending completion of a background check.