The Panthers have their fourth candidate for their head coaching job, and he'll add a little spice to the process at least.

The Panthers have asked for permission to interview Cleveland  Browns defensive coordinator Rob Ryan for their vacant head coaching job, according to two NFL sources.

The 48-year-old Ryan is the son of legendary defensive coach Buddy Ryan and the brother of New York Jets coach Rex Ryan.

He has 13 years of assistant coaching experience in the NFL, with stints in Arizona (on his father's staff) along with New England, Oakland and Cleveland.

He's by far the most colorful of the four identified candidates, a list which also includes defensive coordinators Ron Rivera (San Diego), Perry Fewell (New York Giants) and Greg Manusky (San Francisco).

-- Darin Gantt and Joe Person