As a warning, this post is really long and has a lot of Gifs.
The Steelers defense had a major problem in 2018 at inside linebacker. With Ryan Shazier gone the Steelers brought in Jon Bostic to play with Vince Williams and the results were not good enough, to say the least. That led to a major investment in the position this offseason. The Steelers acquired Mark Barron in Free Agency, then added Devin Bush and Ulysees Gilbert III in the NFL Draft.