Arizona State athletic director Ray Anderson hired new head football coach Herm Edwards in the hope that Edwards would retain both of outgoing coach Todd Graham's top assistants.

ASU has lost both of those men in a span of four days.

Just three days after defensive coordinator Phil Bennett announced he will not return to ASU despite Edwards' offer to retain him, offensive coordinator Billy Napier has decided to leave the program and accept the head coaching position at Louisiana-Lafayette.

University of Louisiana Announces Billy Napier As Head Football Coach https://t.co/j2zuiqhOSl pic.twitter.com/AzFIRR1GMr — Ragin' Cajuns (@ULRaginCajuns) December 15, 2017

“I wish Bill nothing but the best in his coaching career," Edwards said in a statement. "I can assure all Sun Devil fans that I am working diligently on hiring a coaching staff that will fit what we are trying to accomplish at ASU, led by incredible senior quarterback Manny Wilkins.

"Assistant Head Coach and Running Backs Coach John Simon and Co-Offensive Coordinator and Wide Receivers Coach Rob Likens will be a part of my staff going forward."

Napier, a former assistant at Clemson and Alabama, became ASU's offensive coordinator and quarterbacks coach after the 2016 season. Last week, ASU announced Edwards would retain Napier and the entire offensive coaching staff, and promoted Napier to associate head coach.

Bennett and Napier might not be the only coaching departures for the Sun Devils, as FootballScoop.com reported that other ASU assistants are listening to job offers elsewhere.