Matt Bowen remembers the first day of training camp under Gregg Williams -- the first team drill, actually. This was 2004, when Bowen played safety for the Washington Redskins. They were coming off a 5-11 season under the easygoing Steve Spurrier, who was replaced by the legendary Joe Gibbs and his new sheriff on defense, Williams. They started with a 7-on-7 period. Pretty routine. Nice and easy. Pitch and catch.

Except Williams instructed his defense to blitz the quarterback -- all seven defenders.

"I've never seen Mark Brunell look like that in his life," Bowen recalled with a laugh. "He ended up throwing the ball away. That was the introduction to how we were going to play defense."

Memo to the New York Jets: He's coming for you, this 60-year-old defensive coordinator who flaunts a big résumé, a big ego and big expectations.

Williams, the first hire by new coach Adam Gase, will provide a culture shock to the Jets, who finished 29th in scoring defense, their worst ranking since 1996. He's a high-intensity coach who will create a level of accountability that didn't exist under the previous coaching staff. Love him or hate him, Williams is a must-watch coach, and it will be fascinating to gauge his impact on the four biggest names on defense: safety Jamal Adams, cornerback Trumaine Johnson, linebacker Darron Lee and defensive tackle Leonard Williams.

The anticipated switch to a 4-3 defense, after 13 years of a 3-4 base, could have a profound effect on Lee and Leonard Williams in particular. Let's take a look, with some help from Bowen, who played seven seasons in the NFL (two under Williams) and now works as an ESPN NFL analyst.

Leonard Williams: In all likelihood, he'd be the 3-technique in the four-man front, meaning he'd line up on the outside shoulder of a guard. The position is designed for the player to get upfield and make plays, as Los Angeles Rams star Aaron Donald did as the 3-technique under Williams in 2015 and 2016. Hall of Famer Warren Sapp made the position famous during his days with the Tampa Bay Buccaneers.

The feeling in the organization is the new scheme can unlock Leonard Williams' potential. Despite solid play over four seasons, he has managed only 17 sacks. An aggressive, one-gap scheme can help with the sack numbers, but it won't be a cure-all because the change isn't as radical as you might think.

In Todd Bowles' hybrid system last season, Williams played 620 of his 822 snaps as an interior lineman -- left/right tackle and nose tackle, per ESPN Stats & Information data. In the season finale against the New England Patriots, he played no fewer than 23 snaps as the 3-technique. All told, he recorded 2.5 sacks as a tackle, 2.5 as an end.

It really comes down to the individual player. For instance: Trevon Coley was the 3-technique for Williams last season with the Cleveland Browns, and he managed only a half-sack.

"I still think you’ll see him rush outside at times," Bowen said of Williams. "I think Gregg will try to use him as an interchangeable piece along the defensive front. That's one of the areas the Jets need to upgrade; they need to add some edge rushers. If you put Leonard as a 3-technique, now imagine if you have a pretty consistent edge rusher outside of him. It's going to create more one-on-ones inside for Leonard Williams."

Lee: He could be the biggest beneficiary of the Gregg Williams scheme. Undersized as an inside linebacker in the 3-4 scheme, which caused him to get swallowed up against north-south running teams, Lee will feel liberated in the new defense. He will have more opportunities to play in space, where he can excel because of his athleticism. You saw glimpses of it last season, especially in pass coverage (three interceptions). Under Williams, he can be a run-and-hit linebacker.

The question is whether he plays the middle (Mike) or weak side (Will). Bowen said Lee might be a better fit in the middle because Williams has been playing more Cover 2 than he did in past years, and Lee "can run the middle of the field in Cover 2 as a middle linebacker," he said. "You might see him doing that more in sub packages. You can also use him as a blitzer from the middle-linebacker position."

Like Leonard Williams, Lee is entering the final year of his rookie contract. (The Jets have yet to exercise their fifth-year option for 2020.) His once-promising 2018 season ended with a four-game substance-abuse suspension, raising questions about his maturity. Williams and Lee were general manager Mike Maccagnan's first two first-round picks, and the organization is entrusting Gregg Williams to maximize their potential before it's too late.

Adams: He should love Williams' coaching style because it mirrors the way he plays: relentless. He's a do-everything player who should be featured in the new system.

"If you watched his film this year, you know he can be one of the top safeties in the NFL," Bowen said. "There’s no question about that. In this scheme, he can do a lot of different things. I think it goes back to his scouting report coming out of LSU. This was a safety who could cover down, who could play over the tight end and who could match up with a running back. Plus, he had the footwork of a corner at times. He could play in the slot. And he finds the ball. He’s around the football. Guys that are around the football, that doesn’t happen by accident."

Williams will love Adams because he's a smart player who never lets up. The man actually tackled people in the Pro Bowl, for crying out loud.

Johnson: He knows Williams better than anybody on defense because he played for him, 2014 to 2016 with the Rams. He made a lot of money in that scheme -- two franchise tags, plus a $34 million guarantee from the Jets. Johnson's play slipped last season, but maybe he can rebound under the fiery Williams, who won't tolerate a lack of focus.

"He didn’t play his best ball last year -- everyone understands that -- but he gets a fresh start," Bowen said. "I think he's the perfect corner if you play Cover 2, in my opinion, because of his frame, his length. He can be a physical player who can jam at the line of scrimmage and sink and get his eyes on the quarterback. But he’ll be asked to play man coverage as well, and he’ll be asked to play man coverage with no help. That’s part of the defense. The skill set is still there. Maybe this is a situation where, working under Gregg and fine-tuning his technique, he can get back to what he was."