The New Orleans Saints are evolving.

At their core, they haven't changed much since coach Sean Payton and quarterback Drew Brees arrived in 2006. The Saints are still led by a dynamic passing offense that toys with opponents inside the Mercedes-Benz Superdome, where New Orleans was 8-0 last season.

But the Saints will win the NFC South this year because they might just have the best defense in the division, too. Adding three-time Pro Bowl safety Jairus Byrd and future Hall of Fame cornerback Champ Bailey further bolstered a young defense that had a breakout year in 2013 under new coordinator Rob Ryan.

Meanwhile, New Orleans has also been embracing a more traditional run game while parting ways with offensive weapons like Darren Sproles and Lance Moore.

The Saints are showing a New England Patriots-like ability to keep adapting to stay on top.

"Everybody's always looking for ways to reinvent themselves, to improve themselves, without losing who they really are," said ESPN analyst Louis Riddick, who believes New Orleans is doing just that.

Safety Jairus Byrd, who had four interceptions and a forced fumble last season with Buffalo, should help the Saints cause more turnovers. Tom Szczerbowski/Getty Images

"This is one of my favorite teams to watch. I like their style," Riddick, a former personnel director for the Philadelphia Eagles, said of the Saints. "Multiple is a big word in my vocabulary when it comes to football. And they're multiple on both sides of the ball. They can run it or throw it. On defense they can sit back and play zone or pressure you. I like that about them."

The Saints have only seven players remaining from their 2009 Super Bowl team. But New Orleans still should be considered a bona fide contender to get back there five years later.

"I like what they're doing," Riddick said. "I think they're positioning themselves well to make sure that they stay among the heavyweights in the NFC and try to knock some of them off and get back to the big game."

The Saints' defense was surprisingly sensational last year, led by breakout seasons from pass-rushers Cameron Jordan and Junior Galette, cornerback Keenan Lewis and safety Kenny Vaccaro, among others. They ranked fourth in the NFL in yards allowed (305.7 per game) just one year after setting the record for most yards allowed in a season (440.1 per game).

But just as surprisingly, the Saints decided that wasn't enough.

Although conventional wisdom in New Orleans has always been that the Saints just need to be decent on defense to complement their high-powered offense, the team didn't feel that way. Especially after falling victim to the Seattle Seahawks' dominant defense twice last season.

When Payton was asked in his season-ending news conference if there was less of a need to improve the defense than ever before, he quickly shot down the idea.

"I think we try to pay attention to what is winning, who is winning," Payton said. "I think you study the San Franciscos and the Seattles, and you recognize that there is still this formula that has won in our league for a long time. And that is your ability to stop the opponent ... and then have balance in both the running and passing game."

So the Saints went all-in with a six-year, $54 million deal for Byrd. He's a ball-hawking safety who should help in the one area where the Saints' defense struggled last year: forcing turnovers.

Mark Ingram carried 18 times for 97 yards and a touchdown in the Saints' playoff win at Philadelphia. Howard Smith/USA TODAY Sports

Offensively, Payton also seems to be embracing that pass-run balance as much as ever. The Saints rode the run game to their first road playoff win in franchise history. They're clearly intent on finding more touches for emerging running backs Khiry Robinson and Mark Ingram, who led the way that night in Philadelphia. That was one of the reasons for the Saints' decision to trade Sproles, a veteran runner/receiver, to the Eagles.

"You want to kind of be like a chameleon from week to week and do whatever is necessary to win a game, depending on what your opponent doesn't do very well," said Riddick, who remembers the Saints having a better pass-run balance when they steamrolled his Eagles during the 2009 season. "[Patriots coach] Bill Belichick has been lauded for that for years."

It's no coincidence that Payton and Saints general manager Mickey Loomis are being credited for some of the same things as Belichick. Ever since Payton arrived, they have talked openly about modeling themselves after the Patriots organization in many ways.

"What they're doing is [Patriots-like]," said former Saints and Patriots fullback Heath Evans, who now works as an analyst for the NFL Network. "And Sean's never really shied away from, 'Hey, what the Patriots do, it works. So why not to the best of your ability, with your own talent pool and your own system of thinking, try to copy what they do?'"

Evans also pointed out that copying the Patriots' model means borrowing from other teams, as well.

"You've got to go with the flow of this league. And what Seattle's done, they're really the ones that everyone needs to try to be copying," Evans said. "Because they can beat you in 15 different ways. Their quarterback doesn't have to play well to win."

In that same postseason news conference back in January, Payton also shot down another reporter's question, when he was asked if the Saints' "window of opportunity" might be closing as many of their longtime stars get older.

"Honestly, the 'window,'" Payton said, "as long as I am the head coach here, we are trying to slam it open always."