Article is about a month old, but somewhat of an answer without the specifics you may be looking for...
"J.J. Wilcox has been a huge disappointment for the Pittsburgh Steelers since arriving via trade at the end of the preseason. Expected to be a stabilizing force for their secondary, the pass-defense has actually been great... no thanks to Wilcox. His playing time has been reduced each week, and now, it seems, we have a change on the depth chart.
Chris Adamski of The Tribune-Review reports that Robert Golden, not Wilcox, seems to be the No. 3 safety on the depth chart at the moment.
That shouldn't come as any sort of surprise to those who have been watching the games. Golden played 33 defensive snaps against the Lions on Sunday. That's a lot even for a No. 3 safety, proving that the Steelers are gaining more and more faith in him as potentially big part of their defense even with Mike Mitchell and Sean Davis entrenched as the starters. Moving forward, it seems as though those three safeties will be the rotation.
Wilcox, on the other hand, played only one defensive snap on Sunday. He has played nine snaps in the past four weeks after playing a ridiculous 69 against the Baltimore Ravens the week before that stretch started. The Steelers have seen what Wilcox has to offer and have chosen to go in a different direction.
The Steelers have such a dominant pass-defense this year that shuffling parts around the back end likely won't have a major impact, but Mitchell and Davis could both easily get injured. If Golden has outplayed Wilcox so far, he deserves to be the Steeler to step up should a new starter be necessary.
Wilcox was an aggressive move to try to upgrade the defense right now. It was the right attitude for the Steelers, who hit a home run in that regard with the signing of Joe Haden, but ultimately Wilcox just didn't live up to expectations. He'll likely be a backup and special teams player for the rest of the year."