Here's the thing if the Bengals lose Mike Zimmer to a head coaching vacancy. If he leaves, other Bengals assistants could go with him. According to Adam Caplan with ESPN's NFL Insiders show, Zimmer had tabbed running backs coach Hue Jackson as his offensive coordinator and linebackers coach Paul Guenther as his defensive coordinator last year when he was doing the interview circuit for head coaching vacancies.
Had he gotten a head coaching job last year, Mike Zimmer targeted Hue Jackson (OC) and Paul Guenther (DC) as his coordinators.— Adam Caplan (@caplannfl) January 6, 2014
And that might still be true today.
Still is. RT @caplannfl: Had he gotten a head coaching job last year, Zimmer targeted Hue Jackson (OC) + Paul Guenther (DC) as coordinators.— Mike Garafolo (@MikeGarafolo) January 6, 2014
Assistant coaches can't leave, unless it's for a head coaching vacancy, while under contract. Though both would be given promotions by leaving the Bengals, Cincinnati would have to let them out of their existing deals first. However, it's believed that most assistants (non-coordinators) are given one-year deals, usually prior to the team announcing their coaching staff (end of January to late February).
If the above scenario plays out, the Bengals could be looking for a defensive coordinator, running backs coach and linebackers coach. The irony is that if Gruden and Zimmer both leave, Jackson and Guenther would be heavy in-house candidates to replace them as offensive and defensive coordinators.