Commanders fire defensive line coach Sam Mills III, promote Jeff Zgonina

“There was a little bit of difference in the philosophy,” he said, declining to offer specifics. “[This was because of] something that I’ve observed, and [I] just felt that this … needed to be done.”

Jeff Zgonina, the team’s assistant defensive line coach since 2020, was promoted to replace Mills.

In Mills’s two full seasons, the star-studded line did not live up to expectations. Injuries and a lack of discipline hurt the unit, and early last season Rivera criticized star ends Chase Young and Montez Sweat for not playing their assignments consistently as the line struggled to generate pressure and contain opposing quarterbacks.

Over the weekend, Rivera excused Mills from practice so he could go to Canton, Ohio, for his father’s posthumous enshrinement to the Pro Football Hall of Fame. On Monday, Mills returned and coached his group. The next day, Rivera fired him before the team’s 9 a.m. practice.

Rivera said he did not consult the players before he made the decision. He said it was “very difficult, very difficult” to fire Mills, who spent the first 15 years of his career with the Carolina Panthers and worked on Rivera’s staff in Carolina from 2011 to 2019. Mills was among Rivera’s first hires with Washington in January 2020.

Shortly after Rivera was hired, defensive coordinator Jack Del Rio changed Washington’s scheme from a 3-4 to a 4-3. This meant the defensive line switched techniques, employing a more aggressive, upfield style. Some players disagreed about which approach was better and that created friction, according to three people with knowledge of the situation.

In 2021, the line underperformed, the players remained divided, and Mills struggled to control the room, two people said. The tension boiled over in December. In the second quarter of a blowout loss at Dallas, Mills told Daron Payne to come off the field for Tim Settle but Payne refused, two people said. Later, on the sideline, defensive tackle Jonathan Allen criticized Payne, Payne poked Allen, and Allen swung at Payne — even though Mills had put his arm between them.

Early in the offseason, when Rivera met with each of his coaches, he told Mills he needed more from the line, one person said. Washington also changed personnel — Matt Ioannidis and Settle out, second-round pick Phidarian Mathis in — but by early August, it still wasn’t enough. Rivera decided to make one more change ahead of his crucial third year.

After speaking with Mills, Rivera met with Zgonina, then the linemen. After six years in Washington, Allen said “there [are] very few things that can surprise me,” but the timing of Mills’s firing was one of them. He said he had “no idea” it was coming.

“At the end of the day, it’s sad,” Allen said. “Me and Coach Sam were…