Mike Florio runs down the top five NFL head coaches whose jobs are most in jeopardy after a quarter of the season. Defensive breakdowns could hurt Chan Gailey in Buffalo. Jason Garrett may prove a victim of mediocrity in Dallas. Ron Rivera joins his GM on the hot seat in Carolina. Andy Reid’s decision to ice the kicker isn’t helping his standing in Philadelphia. Rex Ryan’s job security is slipping away as the Jets’ season unravels. Finally, Pat Shurmur is under the fun with Cleveland still winless.