In 2012, the Washington Redskins rode the backs of rookies Robert Griffin III and Alfred Morris on offense and turned their fortunes around by going 10-6, winning the NFC East and reaching the playoffs for the first time in five years.

This season, as the team tries to take the next step forward in its development and return to the playoffs in consecutive years for the first time in 21 years, it appears poised to use rookies in prominent roles again — this time on defense.

Through one week of training camp, it has become evident the Redskins’ 2013 draft picks for the secondary , cornerback David Amerson, free safety Bacarri Rambo and strong safety Phillip Thomas, will be used sooner rather than later — and possibly, immediately — in an attempt to improve last season’s 28th-ranked defense.

Rambo, a sixth-round pick out of Georgia, has taken every first-team snap at free safety. Amerson, a second-rounder out of North Carolina State, has taken more first-team snaps than any cornerback in camp — sharing the field with veterans DeAngelo Hall and Josh Wilson at times and other days playing in place of them. Meanwhile, Thomas — a fourth-rounder out of Fresno State — opened camp low on the depth chart but has begun to climb the ranks.

Anything can change between now and Sept. 9 when Washington opens the season against Philadelphia. But if it opened today, Rambo and Amerson would start. Although inexperienced, both represent their team’s best — and in some cases, healthiest — options at their respective positions.

The Post Sports Live crew debates whether the Redskins defense will be more susceptible to the run or the pass in the first part of the season with injuries to Keenan Robinson and Adam Carriker and Jarvis Jenkins’s four-game suspension. (Post Sports Live)

“We’ve got to rely on them,” Wilson said. “We relied on two rookies last year to lead our team on offense, and now we’ve got to rely on these two on defense. They have to be ready to step in play. Nobody’s a rookie when you step on the field. Everybody’s just another man on the field.”

Blessed with size and speed, Amerson has displayed ability to both effectively jam receivers at the line and quickly adjust to pass routes. Coaches and veterans have described him as the most talented corner on the team.

Meanwhile, Rambo boasts a combination of speed, impressive ball skills and playmaking ability that the other free safeties lack. While Thomas doesn’t have Rambo’s range, he is a natural at strong safety because he has good instincts, is comfortable playing in the box, and is a fearless hitter.

On Wednesday, Thomas got his first action with the first unit, and during the two-minute drill simulation in which he, Rambo and Amerson shared the secondary, the defense thwarted the offense’s attempt to drive downfield. He got more first-team action the next day.

“They are talented. That just sticks out,” quarterback Rex Grossman said. “I think Amerson is going to be a great, great corner. You can just tell by the way he reacts to certain routes. His closing speed, you’ve got to be aware of him. In [organized team activities], I was more aware of him than some other players. . . . The two safeties are very aggressive, and they’ve made some plays. Our defense is looking pretty legit. Our defense has youth and experience, and everyone is talented.”

Even before training camp began, defensive coordinator Jim Haslett predicted that all three rookies would play a lot this season. He didn’t commit to any as starters, however.

Secondary coach Raheem Morris doesn’t have an issue with starting rookies. In 2007, while he was an assistant for Tampa Bay, he started Tanard Jackson at free safety. The next year, he started rookie Aqib Talib at cornerback. Two years later, Morris started Cody Grimm at free safety.

Jonathan Forsythe talks to “RG3: The Promise” author and Post sports writer Dave Sheinin about what is next for Robert Griffin III and the Redskins. (Post Sports Live)

But can a team win with multiple rookies starting in its secondary? Will inexperience outweigh talent? Redskins coaches don’t know the answer yet, because next to no one has tried it.

A rare occurrence: The 1981 San Francisco 49ers started three rookies — Ronnie Lott (a future Hall of Famer) at left corner, Carlton Williamson (two-time Pro Bowl pick) at strong safety and Eric Wright (two-time Pro Bowl pick) at right corner. San Francisco’s defense ranked second in the league, and the 49ers went on to win the Super Bowl.

But veteran Redskins believe this season can represent another such instance.

“The 49ers did it. Why can’t we?” defensive captain London Fletcher said. “They’ve come in and acclimated themselves well to the National Football League from OTAs to minicamp, from minicamp until now. You have to go through some growing pains. But [Amerson and Rambo] have the talent to run, they’ve got great ball skills and now it’s just a matter of playing a technique the way the coaches want them to play it and get used to the speed of the NFL.”

He added: “Obviously, if you’ve got a rookie on one side and a seasoned veteran on the other, then [opposing quarterbacks will] probably go after the rookie until they prove they can make plays. That’s just the nature of the business. But again, I don’t think teams can say play in and play out that they’re going to target this guy because we mix up schemes so much that you wouldn’t know what we’ll always be doing.”

The Redskins rookies remain undaunted.

“I feel like I’m ready. I feel prepared,” Rambo said. “I’ve got a great group of guys in front of me that are going to help me stay on track, and I’m going to be back there to make plays for them.”

Amerson agreed.

“We all have the same mind-set,” he said. “I know Bacarri didn’t come in here to sit the bench or watch anybody else play that position, too. We all are aiming to start. It’s just that we have that mind-set of go out there, show what we’ve got and hopefully it shows and we’re out there Game 1.”

Every day represents another proving day for the rookie defensive backs, but the true test will come in preseason games — the first on Thursday night in Nashville. There, Redskins coaches will get an idea of exactly how capable the rookies are of making an immediate impact.

“It’s a start,” Coach Mike Shanahan said of the strong practice performances. “. . . That is why you practice, to give them a chance once they do get in these game situations to show what they can do, see if they can make plays, see if they can eliminate mistakes, how do they play when the lights are on. That is the fun part once we start those preseason games.”