It isn’t that hard for NFL officials to explain away the 9.7 percent decline in its television ratings this season (which followed an 8 percent drop in 2016). Everyone is watching less network TV, they can say, and ratings are down for programming across the board.

But new poll results from the Wall Street Journal and NBC News, released just two days before the Super Bowl, might be a little tougher to dismiss.

In a survey of 900 adults conducted Jan. 13-17, the two news organizations found that the number of adults who say they follow the NFL closely has dropped 9 percent since 2014. But that might not even be the poll’s worst revelation for the league, because it also found that only 51 percent of men aged 18 to 49 — the league’s core audience, in other words — say they follow the NFL closely, a 24 percent drop from four years ago.

The poll did not ask respondents why they are following the league less than before, but a separate set of questions may provide at least part of the answer. According to the poll, 53 percent of mothers said they would encourage their child to play a sport other than football due to concerns about concussions, up from 40 percent in 2014. Of the poll respondents without children, 49 percent said they would encourage their child to play another sport, up from 43 percent four years ago. Fewer poll respondents think the NFL is taking meaningful action on head injuries, as well: Only 47 percent think so, a 12 percent drop from 2014.

The NFL has gotten its share of negative publicity this season thanks to a perfect storm of events: players protesting and President Trump criticizing them for it, throwing gasoline on an already fiery debate; injuries to star players; the league’s baffling inability to pin down what, exactly, constitutes a catch; unappealing matchups for nationally televised games; teams either fumbling or ignoring the league’s protocol for dealing with head injuries. So the results of the poll, which was taken at the end of what has been a trying season for the league, perhaps shouldn’t be all that surprising. Nevertheless, it’s another data point in what is becoming a growing collection of bad news for the NFL.

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