No wonder NFL sponsors like Papa John's are starting to panic: At the halfway point of the 2017 regular season, the league's once-golden TV numbers are still plummeting.

NFL game telecasts averaged 14.772 million viewers during the first eight weeks of the season, according to Nielsen data obtained by Sporting News. That figure is down 5 percent from 15.549 million viewers during the first half of the 2016 season and off 18.7 percent from 18.167 million viewers for the same period in 2015 — before former 49ers quarterback Colin Kaepernick inspired a debate about racial injustice by sitting, then taking a knee, during the national anthem.

Last weekend's action featured two strong games in the late Sunday afternoon window. The Seahawks nipped the Texans 41-38, and the Cowboys beat the archrival Redskins 33-19. Even the magnet Cowboys couldn't save the numbers.

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NFL Week 8 games averaged 12.685 million viewers, according to Nielsen. That's down 6.2 percent from 13.526 million during Week 8 of 2016 and off 25.5 percent from 17.036 million for Week 8 in 2015. Monday night's game, the Chiefs' 29-19 win over the Broncos, was the lowest-rated and least-watched Week 8 "Monday Night Football" game ever, according to Sports Media Watch.

During an investor call Wednesday, Papa John's founder John Schnatter angrily blamed the national anthem controversy, and NFL commissioner Roger Goodell's handling of it, for hurting his chain's pizza sales.

"The NFL has hurt us by not resolving the current debacle to the players' and owners' satisfaction. NFL leadership has hurt Papa John's shareholders," Schnatter was quoted as saying.

Goodell, added Schnatter, should have "nipped" the protests in the bud last season. "Leadership starts at the top, and this is an example of poor leadership," Schnatter said.

Any sponsor unrest is bad news for CBS, NBC, Fox and ESPN, who charge high ad rates for live NFL game telecasts.

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The league's weak TV performance could be attributed to a number of factors (Fox chief executive officer James Murdoch blames "oversaturation" from Thursday night games), but the protests are high on the list.

Like President Donald Trump, Cowboys owner Jerry Jones wants all players to stand for the anthem. Jones has threatened to bench Dallas players who don't. He is leading a mutiny against Goodell, who's more sympathetic to protesting players, according to an article by ESPN The Magazine's Seth Wickersham and Don Van Natta Jr. Trump has urged his millions of supporters to boycott the NFL until Goodell mandates all players stand for the anthem.

Two groups of fans are boycotting the NFL over the protests: #BoycottNFL fans view the player protests as unpatriotic and un-American, while #NoKaepernickNoNFL fans vow to stay away until the free-agent QB lands a job.

A previously scheduled meeting between NFL owners and players was tabled this week after incendiary comments by Texans owner Bob McNair about "inmates running the prison" became public. The relationship between players and owners has become so poisonous that ESPN analyst Charles Woodson, a former star player, refused to use what he called the "O-word" on "Sunday NFL Countdown."

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The NFL needs a numbers rebound during the second half to keep its TV partners and sponsors happy, but with superstar players such as Aaron Rodgers, Odell Beckham Jr. and J.J. Watt out for the season with injuries, that looks like a tall order. Networks might have to start handing out so-called "make-good," or free, ads to make up for shortfalls.

If Jones and Schnatter have their way, the NFL could soon be led by a their-way-or-the-highway commissioner. Stay tuned.