STANFORD, Calif. -- Two brothers, both safeties, play football for teams based just 13 miles apart. But their current situations are very different.

Justin Reid is entering his redshirt junior season at Stanford. He's worked all three of his years on campus under defensive backs coach Duane Akina, evolving into a fixture of the Cardinal's secondary and a Pac-12 all-conference honorable mention in 2016.

Meanwhile, his older brother Eric Reid is spending the offseason down Freeway 101 adapting to the San Francisco 49ers' fourth coaching staff in four years.

"Every year, it's been a coaching change [for Eric] -- I've talked to him about it," Justin Reid said. "It's really irritating [for him]. He has to learn different languages every year. He has to re-establish and reacquaint himself with the coaching staff every year. It's hard for him to know what he can and can't do."

That's not a problem at Stanford, where Justin Reid's communication with his brother has allowed him to develop an extra sense of appreciation for the Cardinal's coaching continuity and resulting success.

The 2017 season will be the fourth for the Cardinal secondary under Akina, the respected assistant who developed an abundance of NFL talent in his previous coaching stops at Texas and Arizona.

"Akina has been with us since we were all freshmen," Reid said. "So he doesn't have to re-teach the coaching vocabulary or the language. He just gets to keep nursing it and allowing it to grow. We get to keep building on what we learned last year."

One of the first fruits of this uninterrupted education process came last season, when the Stanford secondary -- still primarily manned by underclassmen -- nearly doubled its interception total from the year before. It was evidence that the Cardinal, who were athletic but young, were learning a treacherous nuance of pass defense: When to back off, and when to gamble for takeaways.

In 2017, all of the Cardinal's defensive backs will be upperclassmen who've played exclusively for Akina during their college careers.

"This is the smartest defense we've had since I've been here," Reid said. "Our mental capabilities have never been where they are now. It's exciting to see."

Reid will man one of the safety spots. Quenton Meeks and Alijah Holder are expected to be Stanford's top two cornerbacks, but there's much more talent to go around that room -- both in terms of veterans (Terrence Alexander and Alameen Murphy) and among emerging youngsters (Obi Eboh, Treyjohn Butler, Malik Antoine, J.J. Parson and Frank Buncom).

Numerous candidates are vying to grab Dallas Lloyd's vacated safety spot, including Ben Edwards, Denzel Franklin, and Brandon Simmons.

Throughout the history of its program, Stanford has never recruited more touted defensive backs than it has over the past four seasons. Now, the Cardinal hope to fully reap the benefits of that stockpiling effort on the field.

Reid says that continuity under Akina has allowed veterans like himself to spend the offseason helping bring youngsters up to speed. It's also allowed Reid an opportunity to master the mental grasp of other positions around the defense -- and not just his own.

"I feel I'm mentally stronger understanding the positions around me," Reid said. "Cornerback, nickel back, dime, X, outside linebacker -- even defensive line, I'm understanding their stunts, the run scheme, and how their gaps are supposed to fit out. If you know what people around you are doing, you know how to help them out if they make a mistake."

That's a key step for Stanford -- especially since All-American defensive lineman Solomon Thomas is headed to the NFL. Times have changed: The Cardinal, a program that rose to prominence largely on rigid play from its defensive front seven, will now lean more heavily on its secondary.

"Solly is a first-round player," Reid said. "He was a huge part of our defense last year. Not one person is going to be able to take his spot. It's going to be a combined effort. The defensive linemen, the linebackers, and sometimes even us -- the defensive backs -- are going to have to pull together and make up for what he's leaving with."

Physically, Stanford's defensive backs feel that they're up to the challenge of doing the heavy lifting. Reid says the unit has mastered the intellectual side of the game well enough to unleash all of its physical potential in 2017. That was on display in flashes last season -- such as the time when Meeks delivered an electrifying pick six at Notre Dame, or when Reid saved a win at UCLA by separating a receiver from a deep Josh Rosen pass in the waning seconds.

Now, the Cardinal secondary is confident that its mastery will show constantly.

"Everyone here has the tools to be a great D-1 player," Reid said. "You just have to learn the system, learn your place, know you can go and when you can't go. You have to learn when to be safe and when to take a risk. Once you get all that down, it's your chance to make a play. Be a player. It's that time for us now."