The Dallas Cowboys' biggest issue to address this offseason — aside from Dak Prescott's contract — is the defensive side of the ball. Dallas made a move already at defensive coordinator by parting ways with Mike Nolan in favor of former Atlanta Falcons head coach Dan Quinn.

Quinn had a lot of success coordinating the defenses of the Florida Gators on the collegiate level and the Seattle Seahawks during the Legion of Boom era before taking over the Falcons. Perhaps getting back to focusing on just one side of the ball will help Quinn re-gain success.

That is certainly what the Dallas Cowboys are baking on, at least. That said, there is plenty of more work to be done in order to improve the defense.

The secondary is perhaps the most glaring hole, especially with three pending free agents that have played significant snaps for the Cowboys. Defensive line and linebacker both need to be improved, but the Cowboys desperately need to add talent to the defensive backfield.

Veteran defender Richard Sherman could be an option for the Dallas Cowboys.

Trevon Diggs and Donovan Wilson flashed at different points in the 2020 season, but adding more talent to the Cowboys secondary is a must. The Cowboys could very well address the position with their two top-50 picks — including 10th overall — in the 2021 NFL Draft.

Another — or, rather, additional — route for the Cowboys to take this offseason is adding a veteran through free agency. Dallas could decide to bring back Chidobe Awuzie, Jourdan Lewis, or Xavier Woods, or the team could add an outside veteran.

Richard Sherman will be looking for a new contract this offseason. The former Seahawks and San Francisco 49ers defensive back played for Dan Quinn in the Emerald City during his best seasons as a pro. That connection is why many have pointed to the possibility of Sherman signing with Dallas.

Patrik Walker of CBS wrote on the Sherman to Dallas possibility last week. There is certainly a need to add experience in the defensive backfield, and Sherman more than provides that.

Richard Sherman has not been ruled out by the #Cowboys as a possible 2021 free agency signing — I'm told — but a lot would go into potential talks with the All-Pro and, first, the interest must be mutual.

More in my insider notes:

DETAILS ⬇️ https://t.co/7E3XwIKixZ

— Patrik [No C] Walker (@VoiceOfTheStar) January 29, 2021

In Walker's article, it is said that the Cowboys would like to gauge the interest from the former All-Pro defensive back in signing with America's Team. It can't hurt that Quinn is now in the building and in control of the defensive side of the ball/

For while head coach Mike McCarthy remains ice cold at the moment on joining forces with troubled former Seahawks safety Earl Thomas, sources tell CBS Sports, the door is far from welded shut when it comes to Sherman. With the addition of Quinn, the Cowboys have not ruled out interest in possibly signing Sherman in free agency, separate sources affirm, and are actually open to establishing a dialogue with the five-time All-Pro to gauge his interest.

Walker points out that there are some hurdles — such as Sherman's market and his interest in playing for a team that may have a better chance at playing for the Super Bowl next season —  have to be cleared. That said, it is at least encouraging to see that Dallas will reach out.

As good as the Cowboys offense is expected to be in 2021 with Dak Prescott at the helm, Dallas won't be going far without an adequate defense. All levels of the unit have to be improved; but, the secondary, in particular, looks bleak with multiple players hitting free agency.

Richard Sherman would provide the Cowboys with an experienced, battle-tested veteran that has played in big time games. He did miss five games this past season with a calf injury, but he still has some stuff left in the tank. Sherman was a 2019 Pro Bowl selection and a big component of the 49ers defense on their way to a Super Bowl appearance.

Perhaps the relationship between the three-time All-Pro selection and the new defensive coordinator in town will help the Cowboys land an important player in the defensive backfield.

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