The New Orleans Saints tried everything to give the defense a stronger foundation without rocking the one it was built upon.

They brought in new players, introduced a new scheme and added positions to the coaching staff. The playbook was stripped down and the bad elements were shipped out. But in the end, there was no amount of tweaking or renovating that could cover up the issue at the core of it all: Rob Ryan was not getting the job done.

The end came Monday night, when coach Sean Payton announced on his WWL Radio show that Ryan had been fired and senior defensive assistant Dennis Allen would take over as defensive coordinator.

“We just had to, at some point, look closely and give this as an option because the direction we were going wasn’t good,” Payton said.

The move can hardly be painted as rash or reactionary. In fact, some will say it should have been made at the end of last season.

And perhaps the writing was on the wall when Allen was brought in this offseason. While it was painted as giving Ryan more support and a better infrastructure, it was clear from the beginning that Allen, to some degree, was watching over Ryan’s shoulder and waiting in the wings to take over.

But even with the contingency plan in place, which suggested there wasn’t supreme confidence in the team’s ability to turn things around with the old regime at the helm, the Saints were of the state of mind that the issues that plagued the 2014 season were more related to having the wrong personnel and a defense that was too complex for the players.

There was likely a lingering hope that Ryan could return to his 2013 form, when he helped New Orleans have one of the better defenses in the NFL.

The offseason was spent trying to give Ryan the tools he needed to succeed. Assets such as tight end Jimmy Graham and wide receiver Kenny Stills were stripped from the offense and sold off to get better players on defense, all but two draft picks were spent on that side of the ball and the team invested in the bigger, larger cornerbacks it felt it needed to successfully execute the scheme.

The addition of Allen, in particular, was supposed to lead to an uptick. His primary role was working with the secondary, but all the players said he was able to take Ryan’s ideas and coaching points and communicate them in a way that was easier to understand and digest.

Having Allen already in place should help make this transition easier. He’s already well-versed in what the team is doing and could be seen during games signaling in coverages after Ryan called in the play. He’ll now be more involved in coming up with game plans and any other hiccups should be quenched while New Orleans is on its bye this week.

But to get to this point, all of the changes made this season failed to take hold as hoped. It would be wrong to blame Ryan for all of those struggles. It’s not his fault when a linebacker misreads a play or someone misses a tackle. He also couldn’t control that linebacker Dannell Ellerbe and cornerback Keenan Lewis suffered injuries that damaged the defense more than many likely realize.

But he can be blamed for when the defense is ill-prepared for an opponent, as it was against Washington’s screen game during Sunday’s 47-14 loss, or when a player is out of position, or when tight ends, who have caught 58 passes for 768 yards and nine touchdowns against the Saints, are consistently running free.

It was also his fault when the players struggled to line up or a substitution error was made, leaving the defense with 10 players on the field. Those things happened more than they ever should have.

As Payton said last week, at a certain point when a child keeps acting up, it becomes the fault of the parent. It came to a point where Ryan could no longer be allowed to stick around when there were tantrums taking place all around him.

There’s a conversation to be had about whether this move occurred too late. The Saints were not running the same scheme Ryan brought to New Orleans in 2013. During the offseason, the playbook was simplified and the so-called “exotic” way Ryan likes to operate was pushed to the side.

This was supposed to let the players play faster and eliminate the mental mistakes committed by the defense since there were fewer checks and variables that had to be processed on any given snap. The problem is that assignment errors and execution remained a problem, even with a simpler defense.

The other issue is that this was no longer Ryan’s defense. During training camp, and several times throughout the year, Ryan said he was only trying to execute Payton’s vision for the defense.

He also noted before Sunday’s Week 10 game against the Redskins that it was going to take time before the new scheme took hold, saying that it was a new approach that the players were still trying to learn and the coaches were trying to teach.

But even though Ryan boasted during the offseason that he has the ability to teach any scheme, this still wasn’t his scheme. While there were still some elements of the defense that were his, it was no longer his vision and the fit was no longer natural.

It came to a point where patience could no longer be afforded.

Perhaps the Saints should have looked for a coordinator after last season who was a more natural fit to execute the defense the way the team wanted. Maybe keeping Ryan for another season put the defense on a path to doom. Still, getting to a point where the team realized that was not easy.

“I’m disappointed for Rob it didn’t work out,” Payton said. “He’s a fantastic staff guy. He’s a guy that was respected greatly, not only in the locker room but by his peers.”

Given his pedigree, work ethic and how he relates to his players, it’s difficult to blame the Saints for giving Ryan one last chance.

It just didn’t work out, and it was time to admit it.