Tom Pelissero of NFL Network reported Crennel is expected to retire or remain with the organization in a senior assistant role. The 72-year-old's contract is set to expire after he spent the last six seasons in Houston under Bill O'Brien.
Defensive line coach Anthony Weaver will be promoted to defensive coordinator with Crennel exiting, per ESPN's Adam Schefter. Weaver has been the Texans' defensive line coach since 2016. He previously held the same position with the Buffalo Bills and Cleveland Browns.
The Texans fired Senior Vice President of Football Administration Chris Olsen and defensive assistant John Pagano on Saturday, per Aaron Wilson of the Houston Chronicle. O'Brien is expected to continue having final say on all football-related decisions, though he does not have the title of general manager. Pagano spent the last two seasons as a defensive assistant under O'Brien after being let go as the Raiders' defensive coordinator.
The Texans defense finished 28th in yards allowed and 19th in points allowed during the regular season. Football Outsiders' DVOA metric ranked Crennel's unit 26th after a seventh-place finish a year ago. Many of those issues had to do with a struggling pass rush, caused by the departure of Jadeveon Clowney and a midseason injury to J.J. Watt.
If Crennel retires, it'll be the end of a coaching career that began at Western Kentucky University in 1970. His six decades of coaching saw him serve as an assistant under legends Bill Parcells and Bill Belichick, along with head coaching stints with the Cleveland Browns and Kansas City Chiefs.
Crennel earned five Super Bowl rings as an assistant.