While the Bengals offense goes through the growing pains of a rehabilitation, the defense has just put the finishing touches on a facelift that began two years ago with the No. 1 selection of cornerback William Jackson and ended Monday with the unofficial installation of rookie Jessie Bates III as the starting safety next to Shawn Williams.

As the Sept. 9 opener in Indianapolis ticks down to 19 days heading into Tuesday's off day in the wake of veteran safety George Iloka's exit, the Bengals are looking at half their Opening Day starters on a sleek and speedy sports car of a defense graduating from the last three drafts. Instagram-fast nickel pass rusher Carl Lawson (2017) and Fortnite rampaging nose tackle Andrew Billings (2016) are penciled in to prowl up front while the speedy tandem of Nick Vigil (2016) and Jordan Evans (2017) are set at outside linebacker backed up by Jackson (2016) sniffing the Pro Bowl with elite quickness and Bates (2018) patrolling the skies with his snap-crackle-pop-hips.

"At some point," Vigil said Monday, "you have to have faith in the guys you drafted."

And the Bengals are showing faith in fast. Even middle linebacker Preston Brown, an old goat of 25, has caught the eye of coaches who tell you their defense has the one thing they can't teach.

Speed.

There aren't too many things head coach Marvin Lewis likes more than veterans. If he has to see your I.D., you may not see the field. Unless you can run, because even Lewis is going to take speed over skins.

"Billy and Nick and Jordan Evans, we've got some young guys in there that are really running," said defensive coordinator Teryl Austin, breaking down Saturday's pre-season victory in Dallas. "I think that's good for us, because we've improved our team speed, which nowadays teams spread you out and still try to run the ball. You have to have guys that are stout, but also can run. I thought we ran really well. You watch Preston Brown who is a 260-pound guy. He's not young, he's in his fifth year, but you watch him run around and chase the ball, it was impressive."

Even the 6-1, 325-pound Billings is running. Like a man possessed. Weighted down by too many pounds and a rookie knee injury that had yet to respond, Billings struggled last season. But this year he's in shape, so is his knee and he's starting to live up to his draft day clippings of a first-round talent plucked in the fourth.

"He's killing it," Vigil said. "You watch tape from the other day and he's all over the place, cutting off ball carriers, making tackles for loss, taking on double teams. For a nose guard he's doing everything you want him to do."

Austin is also all in on the Baylor strongman after he went home to wreak havoc in Dallas.

"(He) was really disruptive, was able to move in there and get penetration. He was able to hold on to double teams and keep our linebackers clear," Austin said. "That's good for us. That's big for us. Because we know what Geno's going to do. We know what that 3 technique is going to do, and having the nose next to him play well like that, that's problems for people.

"He's worked really hard, and I think one of the things with big guys like him, if you can keep their weight steady and under control, he's able to move. That's the big thing. I know I've talked to him about it, and he's done a really good job of being disciplined with his weight and keeping it kind of in the area that we need it because that's where we feel he's effective, and it's showing up."

But Monday belonged to Bates even though the Bengals probably won't officially make him the starter until director of media relations P.J. Combs unveils the club's weekly news release on Tuesday. If then, since head coach Marvin Lewis holds rookies and depth charts with equal contempt.

Yet Austin is also impressed with Bates' speed and how he has chased down his responsibilities since they took him in the second round back in April, giving them eight defensive starters drafted in the third round or before. They just let go Iloka's steel-belted resume of 76 NFL starts, but the transition has been in gear since three of Austin's first official acts were a February interview of veteran free-agent safety Kurt Coleman, helping decide to draft Bates at No. 54 (their highest pick on a safety in 16 years) and rotate Bates with the 1s in the spring practices.

"When we watched him coming out we knew he had really good movement, really good range. Got around the ball," Austin said. "The biggest issue was how is he going to tackle in our league? He's shown a willingness to tackle. He's been a really solid tackler. Really good angles. Getting guys down. That was the one question we needed answered."

Question 1A is how to replace the experience and command of a guy nicknamed "The General?"

"He's going to grow and make some mistakes. He's going to have some questions and they are going to have some bad plays," Austin said. "It's going to happen. When you look at his upside and ceiling, I really think he has a chance to be a really good player and help us in terms of turning the ball over and as a field general and getting us lined up. I think he is really bright."

The 6-1, 205-pound Bates is a familiar sight to his veteran teammates, thanks to the rotation. Even better, a familiar voice.

"I truly believe in Jessie if that's what we're going with," said cornerback Dre Kirkpatrick, suddenly the senior DB. "We don't really know. They haven't made it official to us yet. Common sense will tell you that's where it's going. I believe in Jessie. Just watching the film, he's popping up. He's all over the field, making great plays. Saturday night he was all over the field communicating. We were doing some great things and that's where we're at right now. That's what we have to put our trust in and belief in."

Bates took time in the rotation to take note of Iloka, the consummate pro, and his approach.

"The leadership role," Bates said of what he absorbed. "Not only in the safeties room, but as a whole secondary. That guy, he did everything. He knew everything. He cleared up the gray areas, made everything black and white. The leadership will be a big thing for me."

As popular as Iloka is in the locker room, his ex-mates found it hard to question the move. Even a guy like Kirkpatrick, who counts Iloka as a close friend and cherished locker mate, knows this is an August they're trying to extend the contracts of Pro Bowl rushers Geno Atkins and Carlos Dunlap and that a 28-year-old back-up safety averaging about $6 million per year doesn't compute.

"Gotta pay some guys. Some guys about to get some big, big money," Kirkpatrick said. "You never know. The team hasn't come and said to us what was their decision based off of. You can only assume. But for the most part, I just feel like at the end of the day they made the best decision for the team."

As stunned as Kirkpatrick appeared, he can also see the youth movement scrawled all over the wall and, in the end, he says that may not be all bad.

Even before Iloka was let go, this was Lewis' youngest secondary in a decade. Until now, there have been only two seasons he hasn't had at least one thirty-something back there, starting with 30-year-old corner Tory James in that Marv Inaugural of 2003. When James left after four years, there was 30-year-old safety Dexter Jackson for 2007. They were callow in '08 and '09, but in '10 they started a pair of 30-year-old safeties in Roy Williams and Chris Crocker and when the 2014 season ended they had three secondary starters at least 30 years of age in corners Terence Newman and Leon Hall and safety Reggie Nelson. When the Bengals chose not to re-up 34-year-old corner Adam Jones in the spring, that left Kirkpatrick the oldest DB at 28.

"That's not a bad thing," Kirkpatrick said. "I feel like it's just breaking old habits. That's how I look at it. You just have to break old habits. It's something they've always done, we've always known them for, so I just look at it as breaking old habits."

He remembers the frustration of sitting behind players he respected, but he was still sitting even though he was a first-rounder in 2012. Current slot corner Darqueze Dennard also sat after getting the call No. 1 in 2014. By the time Jackson began to play last season, he couldn't believe that he, too, at times, sat.

"Hey, maybe it's for the good. I don't know," Kirkpatrick said. "Right now we're just breaking bad habits."

But Robert Livingston, the old geezer of a 33-year-old assistant coach who oversees the safeties, feels blessed by departed veterans like Nelson and Jones and now Iloka. Livingston broke into the league as one of Bengals director of player personnel Duke Tobin's scouts and he absorbed the mechanics of NFL defense through coaches like Mike Zimmer, Paul Guenther, Vance Joseph and veteran players.

"When I started coaching when I was 29, I didn't know what I didn't know," Livingston said. "George had lived it (as a player). "I'll be thankful to him forever for how he made me a better coach because I had a veteran who was open. 'This is what I'm looking at.' The back and forth was very good that way. He's helped me more than I've probably helped him in terms of how to communicate. He's made the room better than he found it. That's what you want to do."

Livingston has always been appreciative of how veterans like Crocker, Hall, Nelson and Adam Jones set the tone for a room where the veterans are generous with their experience and the kids are grateful with their attention. Nelson and Shawn Williams remain steadfast friends. Jones was third-year safety Clayton Fejedelem's sounding board. Kirkpatrick still speaks reverently of Hall and Newman.

And Bates showed he understood Iloka's lessons of leadership when he tweeted a classy thank you to Iloka Sunday night.

"That was my job to kind of send a tweet out," Bates said. "You've got fans who kind of picked sides of where I'm a Jessie Bates fan or a George Iloka fan. The way I look at it, I'm thankful for him for helping me make this transition so much smoother than other rookies have. George left this place better than he found it. You can't ask for much more."

But Bates knows they will.