The first major domino has fallen in Miami, and now the watch begins for the second.

Chris Grier is out as the Dolphins’ general manager one day after a humiliating 28-6 home loss to the Ravens on “Thursday Night Football,” with owner Stephen M. Ross labeling it a mutual split.

Embattled head coach Mike McDaniel is safe through the season, though, per ESPN.

This season marked Grier’s 26th with the franchise, and he had served as the team’s general manager since 2016 and top football operations executive since 2019.

Miami went 77-80 in his tenure, including this year’s 2-7 mark, and made the playoffs three times, losing in the wild-card round in each instance (2016, 2022, 2023).

Champ Kelly is taking over as interim general manager and there will be a search for a full-time person.

“As I assessed the state of the team and in my discussion with Chris, it became clear to both of us that change could not wait,” Ross said in a statement late Friday morning.

“We must improve — in 2025, 2026 and beyond — and it needs to start right now.”

The Dolphins seemed like a team on the rise not too long ago, making the playoffs from 2022-23 in the first two seasons under coach Mike McDaniel, but the wheels have fallen off.

Cracks started to show last year when Miami went 8-9 with $212 million quarterback Tua Tagovailoa being sidelined for six games and Tyreek Hill not producing like in years past.

This offseason featured a mass exodus of veteran players, with Jalen Ramsey, Jonnu Smith and Calais Campbell all leaving the franchise, while star offensive tackle Terron Armstead retired.

A roster lacking has struggled this year, with Tagovailoa looking nothing like a franchise quarterback, the defense having more holes than Swiss cheese and Hill suffering a season-ending and potentially career-ending injury in a Week 4 win over the Jets.

Boos rained down on the Dolphins during Thursday’s no-show, and this firing could be the signal of sweeping changes coming to an organization that hasn’t won a playoff game since 2000.

Grief also served as an area scout, national scout and director of college scouting during his tenure.

“I have always been and remain committed to building a winning team that consistently competes for championships. I am incredibly proud of our leadership as an NFL organization and our continued commitment to the community, but our performance on the field and our team-building process have not been good enough,” Ross said. “There are not excuses. I want to thank the fans for their continue support and passion for the team. You deserve a championship-caliber team you can be proud of.

“There’s much work ahead to return the Dolphins to sustained success, and that work begins now, finishing the season strong, evaluating all areas of our football operation, and moving forward with a clean vision for the future.”

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All eyes now fall on McDaniel, the once-wunderkind who is now guiding a rudderless ship.

He’s 30-30 leading the team, but just 10-16 over the last two seasons and questions have risen about his ability to lead a team and create a culture of toughness.

NFL Network’s Ian Rapoport reported before Thursday’s game that McDaniel’s status was “firmly” up in the air and on the hot seat, so to speak, though he did not sense an imminent move.

He noted that Ross “likes him, believes in him and has invested in him,” with the coach reportedly under contract through 20218, and these remaining games will determine McDaniel’s future.

“Here is how McDaniel is going to be judged,” Rapoport said. “How do the players respond? What is it like in the locker room? Do they keep playing for him or do they not and you see it. That is going to determine whether he keeps his job.”

If Thursday’s effort is any indication, McDaniel may need to update his resume.

The Dolphins return in Week 10 at home against the Bills.