He's gone. The cornerback the Bills drafted 10th overall in 2012 no longer exists. That Stephon Gilmore would barely recognize this 25-year-old version. Something happened. Something changed.

As Gilmore enters his fifth NFL season — a contract year — the quiet, reserved corner's new attitude reflects his new goal. And his mission leaves no room for modesty.

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Talk is cheap for an NFL cornerback. That might be why Gilmore in the past has left the jawing to the likes of Josh Norman and Richard Sherman, no strangers to the best-corner-in-the-league debate table. It's also why Jeremy Boone was a bit surprised by Gilmore's answer when the CB was asked about his focus going into the 2016 season.

"Without any hesitation — any hesitation," stressed Boone, a do-it-all, Charlotte-based performance coach who works with NFL players among other professional athletes. "He said, 'My mission is to be the No. 1 corner in the NFL.' ... He paused, he said, 'Not the No. 1 zone corner, I want to be the No. 1 shutdown corner in the NFL.'"

That's much-needed good news for an organization nearing a state of preseason panic. Having lost Reggie Ragland for the season, Shaq Lawson for a good portion of the season and Marcell Dareus for four games, Buffalo's defensive expectations have been curbed.

Gilmore's continued presence, though, is a relief. He told Sporting News he's expecting to have his best season this year — a smart, calculated prediction.

"I had my best offseason," he said."I feel like I’m in the best shape since I’ve been (playing) football."

According to Pro Football Focus, Gilmore has improved significantly each season, from a -2.4 overall rating in his rookie year to an 8.5 in 2015. Only three players on Buffalo's defense — Dareus, pass rusher Jerry Hughes and breakout rookie corner Ronald Darby — received higher overall grades last season.

Haven't noticed? Gilmore isn't surprised.

"Me Being in Buffalo, a small market, it’s kind of hard, media wise," he said. "I can be doing the same thing as Patrick Peterson, but I’m not going to get the attention."

Coach Rex Ryan thinks Gilmore's less-than-staggering interception numbers paint a false picture of mediocrity, even though nine picks in four seasons are nothing to be ashamed about.

"Where people miss it sometimes is, how many balls get caught on him? They don't complete passes on him," Ryan said last February of Gilmore. "He might not get all the interceptions ... (but) they're not completing balls on him. He's an elite guy."

That said, one would think the Bills wouldn't hesitate to extend Gilmore's contract after picking up the fifth year of his rookie deal. Despite reported negotiations, the team and player have not been able to agree on terms. Both sides are taking a risk, but in this case, the team might be the one to regret the lack of commitment.

"I think if anybody's ready for it, it's a guy like Stephon," said Texans Pro Bowl corner Johnathan Joseph, who also is part of Boone's offseason training group, which operates more like a family than a collection of athletic peers.

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(Tadd Haislop) https://images.daznservices.com/di/library/sporting_news/45/f8/gilmore-boone-williams-082416-haislop_1clkxelfw31jn1k1764yhi6s06.png?t=-1134272858&w=500&quality=80

From left: Stephon Gilmore, Bills; Johnathan Joseph, Texans; Jeremy Boone; Will Johnson, Giants; DeAngelo Williams, Steelers; Zach Hodges, Rams (Photo: Tadd Haislop)

Joseph, a 10-year NFL veteran whom Gilmore has always admired as a fellow, elder South Carolina Gamecock, has been able to advise the younger corner. He's been through the same scenario. Also drafted in the first round, in 2006, Joseph played the first five years of his career in Cincinnati before he and the Bengals failed to reach an extension.

"I’ve seen both sides of it," Joseph said. "There was a point in time I never wanted to leave Cincinnati. Now I’ve gotten to where I don’t want to leave Houston.

"You have to be mentally strong and believe in your worth. Sometimes you look at it and say, ‘why me.’ They can’t afford you or they want you at a certain number. It’s something you have to pray about, weigh on, take everybody’s advice that’s around you, in your corner. Because that’s sometimes a life-changing decision that you make."

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But for Gilmore, regardless of who gives him his next contract, a life-altering decision has already been made.

Boone isn't sure what changed for Gilmore; why he all of the sudden is this driven to become the best at his position. The contract certainly plays a role, as it does for every player in such a situation. Another theory is the success of his peers ... or, in the context of this collection, his offseason family members. In Boone's group with Gilmore are Broncos safety and Super Bowl-champion Darian Stewart, Steelers running back DeAngelo Williams, Vikings cornerback Captain Munnerlyn, Giants fullback Will Johnson and Joseph, among others. All those guys' teams at least made the playoffs last season (Johnson was with the Steelers). Gilmore's Bills did not.

A third factor might be the birth of his son Sebastian, aka Bash, about a year ago.

"Steph said, 'I want to make sure I set that example of what it takes to be the best. I want him to know that,'" Boone recalled.

When Gilmore explained his goal before beginning offseason work, Boone made sure expectations were clear for their second offseason together, especially after the first, 2015, "wasn't phenomenal."

"There are some things that have to change this year," Boone said he told Gilmore. "In terms of not just taking care of your body and what you eat and sleeping, but every single area of life for you has got to be able to upgrade ... I’ll be darned if he wasn’t the first to get there and last to leave.

"Low and behold, he did it."

You might remember Gilmore skipping the majority of Bills OTAs a few months ago, a move many assumed was related to ongoing negotiations at the time. Turns out he had good reasons to train in Charlotte, instead, and they had nothing to do with his contract.

"That was great because DeAngelo (Williams) played a big role with me in helping to mentor Steph," Boone said. "Every day DeAngelo was on him. A new side of Steph started to come out where he started to talk a little junk back to DeAngelo, and he never did that.

"And DeAngelo’s like, ‘Ahhh, we’re making a monster!'"

STEELE: How close are Bills to first Super Bowl?

(Jeremy Boone) https://images.daznservices.com/di/library/sporting_news/39/22/williams-gilmore-082416-boone_14us6z2qzsaqt13p1is5y330s5.png?t=-1129802314&w=500&quality=80

DeAngelo Williams and Stephon Gilmore (Jeremy Boone)

To describe Gilmore's newfound mentality, Boone uses a simple analogy: The coach is having to be the breaks, not the gas pedal.

"He’ll call and ask, 'Should I eat this kind of food? Should I use this kind of massage oil? Do I need to go get some extra yoga in?' ... To the point where there’s so many activities he’s asking that I’m having to say no," Boone said. Gilmore never did that before.

The results — Boone describes Gilmore's confidence as far from arrogant, but rather "a fire within to prove a point and achieve his mission" — have been obvious at Bills camp.

One account, from Scott Schild of NewYorkUpstate.com, pretty much said it all: "With Sammy Watkins sidelined, there’s not a receiver on the Bills’ roster who can challenge Gilmore in practice, and he knows it."

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If Darby can build on a rookie season so successful it prompted SN's Vinnie Iyer to rank him among the NFL's top 10 corners, the Bills will have something special in their secondary this season; a cornerback duo few (if any) teams can trump; a duo that undoubtedly will alleviate whatever defensive deficiencies forced upon Buffalo by injury or suspension.

If that happens, and especially if Gilmore achieves his mission, it's on Bills management to preserve that luxury.

"He's earned his payday," Joseph said. "Hopefully it comes in Buffalo, but if not, it doesn’t change who he is as a player. It just changes the uniform he’s wearing."

Make no mistake — Gilmore will continue to do his part. Boone gave him a gold, rubber band that reads "Protect Your Mission; Protect Your Culture." He wears it on his right wrist as a constant reminder of how he now has the support system necessary to keep his fire lit.

"I just had to find the person who pushed me," Gilmore said of Boone. "(And) having somebody like DeAngelo and J-Jo, they help me out a lot."

The group will stay connected throughout the season, even though the only time Gilmore will face one of his mentors is Week 14, when the Bills host Williams' Steelers. He'd love to see Joseph's Texans or Stewart's Broncos in the AFC playoffs. He feels the pressure to meet them there.

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That's why Joseph thinks Buffalo would be crazy not to pay Gilmore. Maybe he's right. If getting dominated by Tom Brady for a decade and a half in the AFC East isn't enough motivation for the Bills to optimize their pass defense, perhaps Joseph can provide the necessary dose of reason.

"He’s gotten better every year," he said of Gilmore. "He’s a great guy. Works hard. Stays to himself. Stays out of trouble. Stays out of the limelight. That’s all you can ask for from a player in this league."

That, and being a monster determined to be the best at his craft. Nobody likes to face that kind of monster.