Falcons owner Arthur Blank, who once promised to leave no stone unturned in trying to bring a Super Bowl championship to Atlanta, is headed back to the rock pile. The franchise just fired the winningest coach in its 48-year history.

Because Blank no longer felt Mike Smith could elevate the team after seven years, he relieved Smith Monday morning, one day after the Falcons were steamrolled by Carolina in a game for the NFC South title. Riding two losing seasons and the clock ticking on the team’s 2017 move in a new $1.4 billion stadium, the team finds itself at a coach-less crossroads.

Blank said the decision to relieve Smith was painful.

“I would tell you that probably, including my 23 years at the Home Depot, this is the most difficult decision that I have ever had to make,” Blank said. “I mean that very sincerely. It was complicated by the deepest respect that I have and we all have for Smitty.”

For now, general manger Thomas Dimitroff, who made some of the personnel moves that might have under-mined Smith’s chances for success, has been retained. But Blank promised an assessment of the entire football operation that will include Dimitroff’s role.

“The assessment has begun,” Blank said. “Where it will end, I can’t tell you. As I said, it may be over at this point. It may not be. We’ll review every part of our football operations and make sure that we have the same standard in place throughout.”

While the firing had been anticipated after the team went through a five-game losing streak, some fans believe the Falcons’ woes runner deeper into the organization, to judge by fans’ cyberspace traffic.

“I’ll echo a familiar sentiment, problems with the Falcons performance go far beyond the head coach,” George Burgan emailed.

Tweeted Drew Flatford from Carrollton, “(Dimitroff) has to go; he’s had control of roster.”

Smith, who posted a 66-46 (.589) record and guided the Falcons to the playoffs in four of his first five seasons, oversaw Sunday’s 34-3 loss to Charlotte at the Georgia Dome, which dropped the team to 6-10. Many Atlanta fans fled the stadium well before the game was over.

“We want to win championships,” Blank said. “We need to win a championship. …We are committed to doing that. That’s the standard of excellence, that’s the standard that we expect from everybody.”

Over his first five seasons, Smith’s teams played solid defense, was rarely penalized and made it a habit of winning close games. He took over after the horrible 2007 season in which quarterback Michael Vick was sent to federal prison in a dog-fighting case and head coach Bobby Petrino quit 13 games into the season.

Smith and his coaching staff helped restore order quickly, going 11-5 with Matt Ryan as a rookie quarterback and advancing to the playoffs. Four years later, they reached the NFC Championship game, losing a 17-point lead in a defeat to San Francisco.

It has been downhill ever since as the Falcons have gone 10-22 over the two subsequent seasons.

Smith, a defensve specialist, was rigid and systematic about how he approached the game and some contend his staff had trouble with in-game adjustments.

“This business does require creativity and flexibility,” Blank said. “Not only from year-to-year, from season-to-season, but from game-to-game and within the game. Somebody who has an adaptive mind, who can think around corners and think ahead in terms of what they may be facing (fits what the Falcons are looking for).”

Filling out a short list of possible replacements, the team has already sought permission to interview Denver offensive coordinator Adam Gase, Seattle defensive coordinator Dan Quinn, Arizona defensive coordinator Todd Bowles and Detroit defensive coordinator Teryl Austin.

Dimitroff, who will be involved in the coaching search, admitted to some personnel mistakes in the draft and free agency.

“We have some good players on this football team and we also know that I have made mistakes,” said Dimitroff, who was not made available to the local media all season. “I know that I’m going to be scrutinized for it.”

Despite the season’s failures, Blank seemed pleased with the team’s current talent level.

“We’re happy with a lot of them, we’ve got a lot of great players,” Blank said. “But do we have as many as we need? Probably not. Do we have holes? Probably, yes. How best to fill them will be in large part up to the new coach.”

The timing is sensitive for the new stadium project. The Falcons next month are set to announce a premium seat license program that will be ground-breaking in this market. However, Blank said the new stadium, PSLs, sponsors nor season ticket-holder unrest played into Monday’s transaction.

“The question was raised if this had anything to do with the new stadium,” Blank said. “No, it had nothing to do with it.”