The Washington Redskins got an upgrade at free safety this offseason by signing O.J. Atogwe.

It shouldn’t take Atogwe — a ball-hawk with great range and an impressive 38 turnovers (22 interceptions, 16 forced fumbles) in the last six years — long to make an impact.

Atogwe also has a good understanding of Jim Haslett’s coverages, having played for him in St. Louis.

But how will the rest of the secondary fare? The Redskins have a good chance of success in that area. But developing chemistry ranks high on the to-do list for the unit, which remains under construction.

LaRon Landry had surgery this offseason to repair a dislocated wrist and also has been receiving platelet-rich plasma treatments to stimulate healing on his right shoulder and the badly strained left Achilles’ tendon that caused him to miss the final seven games of last season.

Landry continued training on his own rather than attend the group workouts his teammates organized, so it’s hard to say how close he is to 100 percent.

If he is recovered he should only build on last season, when in nine games he recorded 85 tackles with an interception and forced fumble. He and Atogwe – who also had scheduling conflicts and wasn’t able to attend any of the player-led workouts – will have to develop chemistry, but safety should be a strength for the defense.

Cornerback is another question area. Yes, DeAngelo Hall returns and is coming off a Pro Bowl season in which he had six interceptions. But it appears that Carlos Rogers, who was actually better in coverage than Hall, is headed elsewhere as a free agent.

Whether the Redskins land Nnamdi Asomugha, another free agent cornerback or decide to go with third-year defensive Kevin Barnes at the spot opposite, chemistry will need to be developed between that player, Hall and the safeties as well.

At linebacker, nearly all of the players under contract – Brian Orakpo, London Fletcher, Lorenzo Alexander, Chris Wilson, Rob Jackson, Perry Riley and rookies Ryan Kerrigan and Markus White — got in some work together this offseason. (Robert Henson was only linebacker who didn’t attend, and even free agent-to-be Rocky McIntosh showed up multiple times).

There is more getting-to-know-you work ahead for the secondary, however.

Hall, Barnes and rookies DeJon Gomes and Brandyn Thompson took reps together during the player-led workouts. And backup safeties Chris Horton, Kareem Moore and Anderson Russell got some work in as well. But the start of training camp will likely be an introduction process as those players and any additions learn their tendencies and the roles Haslett envisions for them.