The Ryan brothers have never been short on confidence, that's for sure.

They've united in Buffalo with head coach Rex creating the position "assistant head coach/defense" for Rob, who was dismissed from New Orleans in 2015 after a 47-14 blowout loss to the Redskins in Week 10.

The colorful duo spoke with The MMQB's Jenny Vrentas recently, when Rob Ryan expressed his excitement to kick the league's rear. He also reflected on his tenure as the Saints' defensive coordinator, particularly the last two years when the team devolved into swiss cheese, allowing 28 points per game.

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"There are two years that don't have my signature on them, and it's the last two years in New Orleans," Ryan said. "And that's just the truth."

Vrentas: It wasn't your defense?

Ryan: Right. And I'm tired of saying it was. It wasn't.

Vrentas: Were you forced to run a different system?

Ryan: No, I'm not going to say I was "forced." I advanced the plan to the best of my ability. All of a sudden, we let some good players go; we changed the system after we finished fourth in the league in defense. I don't know, it just seems strange to me. But I have a lot to prove, and I'm going to prove it. And that's why I came to Buffalo, to be "all in," right here. People can throw stones, but we will be throwing them back at them. They better be watching out.

Ryan suggested that he was tasked with running a Seahawks-style of defense and that led to his undoing. At least one former Seahawk was on board and he performed dreadfully. The Saints signed defensive back Brandon Browner in 2015 and he proceeded to collect an abysmal 21 penalties (accepted) against for 207 yards. "I did the best job I could," Ryan said.

But Sean Payton isn't letting Ryan absolve himself and disputes Ryan's version of what transpired. Payton said in a conversation with ProFootballTalk:

"The idea that it wasn't his defense, or he wasn't in charge of it, is silly.

"When you're struggling as bad as we're struggling for two years, and some of the same problems keep coming up -- you know, 10 guys on the field -- those are things that just are hard to live with."

It remains to be seen how much of a stamp Rob Ryan will be allowed make on the Bills defense. Buffalo has a defensive coordinator (Dennis Thurman) but presumably Rob is going to be something more than Rex's tagalong or just a guy who looks good with flowing gray locks under a headset.

Meanwhile, Rex has always been viewed as a defensive guru, yet the hyped Buffalo's defense took a disappointing step back in 2015, allowing four more points a game than when he arrived.

One thing is certain: These Bills will not be boring.