Miami owner Stephen Ross fired coach Joe Philbin on Monday, four games into his fourth season, and one day after a flop on an international stage helped seal his fate.
Tight ends coach Dan Campbell was promoted to interim coach. His only coaching experience is with the Dolphins, who hired him as an intern in 2010, but the former NFL tight end was poised as well as passionate during a 25-minute introductory news conference.
"I'm not here just to finish the season up," Campbell said. "That's not my plan. We're coming here to win games. It's still early. We have time to turn everything around. But we can't wait."
The Dolphins (1-3) lost their third game in a row Sunday with their fourth consecutive lackluster performance, a 27-14 loss to the archrival Jets in London.
Ross ignored calls to fire Philbin in December after the team faded to finish 8-8 for a second successive season. Doubts only grew this season regarding Philbin's inability to motivate players with his passive demeanor.
Campbel said he respected Philbin but wants to change the culture.
"My vision is a bunch of hard-nosed guys that go out every day for practice and are ultracompetitive," Campbell said. "These are guys that are scratching and clawing, very intense, very heated, and on Sunday it's that same team.
"We are going to play by the rules, but we're going to be much more aggressive. There's always that line: 'This is OK to do, and this is dirty.' I'm not saying we want dirty players, but we're going to walk that line. I don't want us playing on our heels. I want us playing on our toes."
Philbin apparently lost control of his football team before Sunday's loss. During Saturday's walk-through practice in London the Dolphins defense took offense to derogatory comments quarterback Ryan Tannehill made to the scout team defenders and eventually stopped practicing during the dry run for Sunday's game.
Tannehill had committed a couple turnovers early in the walk-through and was bothered by scout team defenders intercepting his passes. During an exchange with linebacker Chris McCain, who picked off a poorly thrown pass, the team's starting quarterback told the defenders "enjoy your practice squad paychecks," a source said.
An altercation ensured, and after the coaches got things under control, the Dolphins defenders aggressively went after more of Tannehill's passes, disrupting the offense's rhythm.
When the defenders were told to stop running full speed during the walk-through the defense stopped running at all during Tannehill's snaps.
Mallett still starting
The Texans are sticking with Ryan Mallett as their starting quarterback despite his recent struggles.
Mallett threw an interception and didn't lead the Texans to any points before he was replaced by Brian Hoyer late in a 48-21 loss to Atlanta on Sunday.
Hoyer threw two touchdown passes and directed three scoring drives late against a Falcons defense that had pulled most of its starters. Hoyer won the job out of camp, but was benched after one game in favor of Mallett.
"He's our starting quarterback," coach Bill O'Brien said of Mallett. "Like all of us, he knows that he has to play better. We all have to do better. He's got to do a better job of throwing the ball more accurately, be more controlled in the pocket, don't turn it over, gets us into the right play, but that's who will start against the Indianapolis Colts."
Mallett has thrown for 720 yards with three touchdowns and three interceptions.
•Receiver Martavis Bryant practiced with the Steelers after serving a four-game suspension for reportedly failing multiple tests for marijuana use.
•The Jaguars placed right guard Brandon Linder on injured reserve because of a shoulder injury.
•Rams linebacker Alec Ogletree, the team's leading tackler, will undergo surgery for a broken right ankle and could be out for the season.
•The Buccaneers waived kicker Kyle Brindz, who missed two field-goal attempts and an extra point during a 37-23 loss to NFC South rival Carolina.
•Bears center Will Montgomery broke his fibula and is out indefinitely.