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NFL teams rarely want to do Hard Knocks, the HBO reality TV show that gives an up-close (and too invasive, in the minds of most coaches) look at training camp. But the NFL views Hard Knocks as one of its key marketing tools heading into each season, and so league rules can compel a team to appear on the show if no team volunteers.

This year, six teams meet the criteria to be forced to do the show: Baltimore, Cleveland, Denver, the L.A. Chargers, San Francisco and Washington.

The teams that have the right to refuse to do Hard Knocks are the teams that have already done the show once in the last 10 years, the teams that have a new head coach and the teams that have been to the playoffs in the last two years. Assuming there are no other head-coaching departures, 26 of the league’s 32 teams fit into at least one of those categories.

So Hard Knocks will have its choice of six storylines: Baltimore’s attempt to get back on top after three straight disappointing seasons? Cleveland’s attempt to turn around from the worst two-year stretch in NFL history? Denver’s likely quarterback competition? The No. 2 team in L.A. trying to get some attention? San Francisco and the emergence of Jimmy Garoppolo? Washington with either a quarterback in Kirk Cousins who just broke the bank, or a new quarterback after Cousins has departed for greener pastures?

One of those storylines will likely be the focal point of Hard Knocks. We’ll see it in seven months.