And it couldn't come at a better time.
While the offense got a boost with the arrival of WR Mike Wallace today, the defense gets one of its cornerstones back in Harrison. The 2008 Defensive Player of the Year missed a decent chunk of time in 2011 after an apparently legal helmet-to-helmet hit from Texans OT Duane Brown broke an orbital bone in Harrison's eye in Week 4.
The Steelers defense ended up being the league's top scoring unit, allowing just 14.5 points per game, but it was middle of the back in sacks (35) and near the bottom in takeaways (15).
Harrison's pass rush and ability to force fumbles should help both of those numbers.
Worilds was the position's top back-up in 2011, filling in both for Harrison and LaMarr Woodley, who missed nearly half the season with a hamstring injury. Worilds had three sacks in seven games.
The re-established depth of the Steelers linebacking unit comes at an excellent time. While neither will play in Thursday's preseason finale vs. Carolina, they still have enough time to prepare for the Week 1 clash at Denver.