The San Francisco 49ers have found themselves shuffling their secondary with some regularity in recent weeks. Injuries have been a major issue, with Richard Sherman, Jaquiski Tartt, and Adrian Colbert all missing time due to injuries. Additionally, ineffectiveness at times from Ahkello Witherspoon and Jimmie Ward have resulted in some changes.

This past weekend, the 49ers rotated Greg Mabin into the cornerback position in the second half. He played 29 snaps, and defensive coordinator Robert Saleh said on Thursday that will continue this week. The coaching staff was pleased with his work in practice thus far and earned an opportunity in their eyes.

“Greg Mabin, over the last few weeks, has been doing an excellent job with his practice habits and being deliberate and he earned the right to at least be part of the rotation with playing time. So, that was more of a testament to Mabin and what he’s been showing at practice, going through his reps, than it is an indictment on anybody else in that DB room.”

The coaches were impressed with the whole picture, with Saleh complimenting his physicality, competitive toughness, and communication skills. He thought it showed up in the game tape, and even though Mabin gave one up, Saleh it was well contested.

One big problem the defense has had is the turnover in trying to figure out how fits where. Saleh is hoping one of the cornerbacks can, “grab hold of [the job] and have a stranglehold on it and not let it go.” He described it as being something for the entire defense where, it’s a challenge, “to grab your job by the neck and choke it out.”

When you have constant turnover on defense, it becomes difficult for the unit to gel. Each player always has their own assignment to handle, but there is a certain chemistry that is critical for a defense to gel into a cohesive dominant unit. Each player needs to step up when it come to the team’s tackling issues, but the overall defensive performance could very well come together once they can get a clear starting lineup and rotation sorted out.

“I think one of the more underrated things that happen, it’s happening throughout the team, it’s a team game, it’s a team effect. So, when you lose players on defense and people are in and out of the lineup, the biggest thing that hurts is the communication part of it. Communication from a defensive standpoint is critical to your ability to have success. When you’re looking at the linebacker’s standpoint, the combination of [LB] Fred [Warner] and [LB] Brock [Coyle], and then Fred and [LB] Elijah [Lee], then Fred and Reuben, Fred and [LB] Malcolm [Smith], the communication part of it, even though they are comfortable with each other, they’re not battle tested together. Same thing at the back-end level. When the linebackers are used to hearing [S Jaquiski] Tartt and now it’s [DB Antone] Exum [Jr.] or [DB] D.J. Reed [Jr.], that combination, there needs to be continuity in there. It’s a trickle-down effect. The biggest loss isn’t so much the level of play because everyone’s expected to perform, that’s the whole next man up. But, what needs to be great is the ability to communicate. That has to accelerate. When one person is gone, the next person has to come in and elevate his ability to communicate so there is no hitch in the defense. So, when you’re having all the mixing and matching, especially between the two safeties and the two linebackers, communication is where it hurts.”