By releasing Darian Stewart on Wednesday, the Denver Broncos signified that it’s time to leave the past in the past.

Stewart and the rest of the “No Fly Zone” played a huge role in Denver’s historic 2015 season. But after three straight years without a postseason appearance, Chris Harris Jr. is the only remaining member of the historic unit, and the Broncos are in a position where the front office needs to prioritize improving the secondary.

Luckily for Denver, there is a surplus of talented defensive backs on the free agent market, making this spring the perfect time to reload.

With that in mind, here are four safeties for the Broncos to pursue via free agency:

Landon Collins

Landing the former University of Alabama star may be a long shot as Collins will be one of the more popular free agents in 2019. If the Broncos are looking to make a splash though, signing Collins would be a massive move for the secondary.

Collins is one of the most complete safeties in the NFL, with the ability to both roam the secondary and be a thumper in the run game. In four seasons with the Giants, Collins never finished with less than 95 total tackles in a single year and his versatility is evident with 22 tackles for a loss, 10 hits on the QB, 32 pass deflections and eight interceptions as well.

Signing Collins would not only help bring stability to the secondary, but would also be great PR for a team that has struggled drastically since winning a Super Bowl under Gary Kubiak.

Earl Thomas

Similarly to Collins, Thomas should have multiple suitors this spring, but the longtime Seattle safety would be a significant upgrade in pass coverage for the Broncos. Thomas is one of the true “ball hawks” in the NFL and has been terrorizing quarterbacks throughout his career.

There may be some concerns about his health after missing 12 games with a fractured leg in 2018, but if he’s good to go, Thomas will be a home run signing for someone.

In 125 career starts, Thomas has 684 combined tackles and 28 interceptions. More importantly though — before injuring his leg — the veteran was playing at an extremely high level in his eighth professional season. In the first month of the 2018 campaign alone, Thomas averaged 5.5 tackles per game and recorded three interceptions.

Teams rumored to be interested in Thomas, include the 49ers and Cowboys, which could drive up his asking price. However, if the Broncos secure a meeting with the three-time All-Pro, Denver should definitely consider bringing him to the Mile High City.

Tyrann Mathieu

Houston is still reportedly trying re-sign the “Honey Badger,” but if he does test his luck on the open market, Denver should be willing to pounce.

The veteran defensive back can line up all over the field and his swagger could help bring an edge back to Denver’s defense. Mathieu is the type of defensive back that not only disrupts an opponent’s game plan, but also helps your team gain a psychological advantage.

Much like Aqib Talib though, Mathieu backs up his talk with incredible play on the field.

If the Broncos want to try and recreate the “dog mentality” that was synonymous with the No Fly Zone, bringing in a player like Mathieu is the way to go.

Adrian Amos

Amos has spent his entire career in Vic Fangio’s system, which makes him a logical target for the Broncos. At only 25 years old, Amos is younger than most of the other safeties on the open market, also helping his appeal; but more than anything, Amos is just an extremely talented defensive back.

The former Penn State standout has been as consistent in coverage as any of his counterparts and he’s proven to be a sure tackler in the open field with 269 combined tackles over four seasons.

If signed, Amos would be a significant upgrade over Stewart — plus the Broncos would benefit from having a veteran on the roster that is familiar with how Fangio prefers to operate.

No matter who the Broncos end up pursuing, Broncos fans can expect a different look in the secondary in 2019. The front office has made it clear that the results have not been good enough in recent years, and change is on the way.