Bengals linebackers coach Paul Guenther is an extremely popular coach right now.
It was learned last year that had defensive coordinator Mike Zimmer been hired as a head coach, he intended to bring Guenther with him to become his defensive coordinator with his new team -- a reality that exists today. It's an ironic situation, to be fair. If Zimmer leaves Cincinnati, Guenther actually becomes the Bengals leading in-house candidate to as the next defensive coordinator.
Now Washington Redskins head coach Jay Gruden is interested in chatting with Guenther about joining his staff, according to NFL insider Adam Caplan.
Presumably the position would be for defensive coordinator.
However, if Guenther remains under contract, neither Gruden nor Zimmer can hire him away from Cincinnati. According to league rules, if a coach is under contract, there is no provision that allows the coach to leave, other than for a vacant head coaching position.
Cincinnati would have to allow Guenther out of his current contract and we don't see that happening with Zimmer's future a little undecided right now. Plus the Bengals have shown a belief of promoting from within, evident by their promotions of Hue Jackson and Kyle Caskey.
On the other hand, if Guenther is no longer under contract (many assistants play under one-year deals), then the Bengals can't block it.