Steve Spagnuolo has been fired after one season as the New Orleans Saints' defensive coordinator.
The former St Louis Rams head coach took charge of the side's defence in the wake of the bounty scandal last year.
Newly reinstated head coach Sean Payton said in a statement: "I personally want to thank Steve and [secondary coach Ken Flajole, who also leaves the franchise] for their contributions during what was an unprecedented 2012 season.
"Philosophically we are changing our defence to a 3-4 alignment, and right now is the best time to accomplish this transition."
The Saints set a new record of most yards allowed by a side in a single season during 2012, and were ranked 31st out of the 32 NFL teams for points allowed per game.
