To quote the rapper Nelly, “It’s getting hot in here.”

NFL training camps are upon us.

And that means hot days leading to on-field fights, contract standoffs between players and general managers, quarterback battles, the fear of season-altering injuries and every player claiming to be in the best shape of his life and primed for a career year.

An average of six teams that were not in the playoffs the prior season have reached the postseason every year since 1990. The journey to identify those improved teams — and which corresponding teams are due to fall off — begins now.