According to Aaron Wilson of Scout.com, former Miami, Cleveland, and Jacksonville defensive end Matt Roth visited the Bengals yesterday. Roth is an eight year veteran who was drafted out of Iowa in the second round (46th overall) by the Miami Dolphins. Last season Roth played in Jacksonville and gathered just 24 tackles and 3.5 sacks.
Jaguars free agent defensive end Matt Roth visited the Bengals, per a league source
Roth has mainly been a rotational player in the front seven, but in 2008 the Dolphins moved him to OLB in their 3-4 defensive scheme and he had a very good year setting his career record for sacks at 5.0 and compiling 53 tackles (46 solo).
The Bengals have been bringing in a lot of defensive linemen (see Derek Harvey and Jamaal Anderson from yesterdays signing extravaganza) over the past week which is likely the result of Frostee Rucker and Jonathon Fanene departing to Cleveland and New England via free agency.
One key point that helped the Bengals' defense finish no. 7 in the NFL in 2011 is the depth of the defensive line and the quality of the players in their rotation. With the Harvey and Anderson signings, even though they are considered to be busts by many because of their high draft positions, the Bengals are effectively replacing the roster slots opened by free agency departures. All of these "draft busts" the Bengals are signing have one significant thing in common: they have yet to be coached by Mike Zimmer. Zimmer has shown that he can take talented, but unproductive, players and put them in a scheme that complements their talents (i.e. Reggie Nelson, Nate Clements, Thomas Howard, Manny Lawson, etc).