Here’s how quickly the best-laid plans can unravel in the NFL:

As recently as Thursday morning, the Dolphins had a dependable front-runner in their quarterback battle and a talented, veteran receiver helping bring along their unproven young guys.

But by the dawn of a new week, David Garrard had a scar on his knee from a fresh surgery, and Chad Johnson had spent a night in jail.

Now, with Johnson gone (dumped unceremoniously by the team late Sunday after being charged with misdemeanor domestic abuse), Garrard sidelined for up to a month and members of his locker room openly critical, coach Joe Philbin faces his first real dose of adversity as a rookie NFL coach.

Philbin met with the media Monday for the first time since jettisoning Johnson, and the room was packed. Hovering above his head while he spoke: Two boom microphones, a constant reminder that nearly every sound he makes gets recorded by HBO’s Hard Knocks.

“It’s not about one person flexing his muscles, or him saying, ‘We’re doing this,’ ” Philbin said, explaining his decision to cut Johnson the day after the receiver was arrested on charges he head-butted his wife.

“It’s just about a fit,” he said. “It didn’t feel like to me that this fit was going to be right for us, for the organization or for Chad. It wasn’t done to send a message. It was done because it didn’t feel right.”

Episode Two of the training camp reality TV show is Tuesday at 10 p.m., and HBO has confirmed the show will give an inside look at Johnson’s final day as a Dolphin.

(The news got even worse for the mercurial wide receiver Monday afternoon as TMZ reported VH1 has decided to pull the plug the reality TV show featuring Johnson and his wife, Evelyn Lozada, who’s pressing charges in the domestic abuse case. Johnson has not commented publicly since his arrest, either verbally or on Twitter.)

But no extra access was needed Monday to get a feel for how some of Johnson’s former teammates took the news.

Karlos Dansby began his day by criticizing Johnson’s quick release to radio host Sid Rosenberg on Palm Beach County’s WMEN-640 radio station.

“It’s going to be a bigger distraction because we let him go,” Dansby said on the air. “If he’s going to be our guy, we have to stand behind him.

“He didn’t get that third strike. That’s just me personally. We’ve been through worse. We’ve seen worse.”

Dansby stood by his remarks when asked about them following Monday’s practice, although he did not repeat them.

Meanwhile, cornerback Sean Smith — who was particularly excited by Johnson’s addition in June and Monday called him “a great person, a great teammate” — tried to keep quiet about the issue, with mixed success.

When asked if he was upset by the move, he chuckled, and then said: “I guess you could say that.”

To be clear, there are plenty of Dolphins players who agreed with the decision to cut Johnson, with one saying privately, “We don’t need no clowns here.”

Yet public criticism of any coach — let alone one just six months into his first top job — is bound to make waves.

“Let’s be honest,” Philbin said. “You have a boss, I have a boss. I don’t always agree with what the boss says every single time. I’m of the opinion you should keep things in-house in that regard.”

If he didn’t know going in, Philbin certainly knows now: Coaching in the modern era is as much about managing crises and personalities as it is about managing a game.

In Philbin’s first team meeting in April, he told his players that crises small and large will inevitably arise throughout the course of a season. The best way to deal with the speed bumps, he said, is to be open and honest with his players.

“If it was easy, everybody would be doing it,” Cameron Wake said, when asked about conquering hardship.

Thanks to Hard Knocks, we will all get a chance Tuesday night to see Philbin’s tough-love philosophy in action.