When the N.F.L. regular season ends, a new season immediately begins. The postseason? No, not yet. First comes the brief but brutal annual season of firing coaches.

Four teams dismissed their coaches on Monday: Marvin Lewis was fired by the Bengals, Vance Joseph by the Broncos, Steve Wilks by the Cardinals and Adam Gase by the Dolphins.

News of the four firings came out in a short window on Monday morning, a particularly ugly hour or two for the members of the N.F.L. coaching fraternity.

Joseph, Wilks and Lewis are black, leaving the number of black head coaches in the N.F.L. at two, Anthony Lynn of the Chargers and Mike Tomlin of the Steelers.