Fox Sports shouldn't celebrate too long about breaking into the exclusive club of NFL Draft TV partners. The league's contracts with Fox and ESPN don't guarantee exclusivity on coverage, sources tell Sporting News, which means NBC and CBS could televise the event in coming years.

The first round of the 2017 NFL Draft was watched by 6.7 million viewers on ESPN and another 2.5 million on NFL Network, according to The New York Times. With as many as six quarterbacks possibly getting selected in the first round next Thursday night in Dallas, and the two teams from the nation's biggest TV market picking second (Giants) and third (Jets), the 2018 NFL Draft is expected to produce record TV audience and ratings.

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And as the annual football festival grows in popularity, some league executives envision the draft potentially becoming the sports equivalent of a U.S. presidential election — a sports event televised simultaneously across most or all of the national broadcast networks: NBC, CBS, Fox and ESPN's sister Disney network ABC.

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This year's event will be televised by a record six TV entities, including two broadcast channels (Fox and ABC) and four cable networks (ESPN, ESPN2, ESPN Deportes and NFL Network). ABC will simulcast ESPN's coverage of Rounds 4-7 on Saturday. That means all seven rounds will air on broadcast television for the first time.

That's one of the key provisos, said sources. If the league's other broadcast partners eventually want the draft, they would likely have to televise it on their main broadcast channels, not their smaller sports cable networks. In other words, NBC Sports would have to show it on NBC, not NBCSN, and so forth. Fox is airing it this year on so-called "big Fox" rather than its FS1/FS2 cable channels.

The NFL declined comment, but if you don't believe the league has bigger and better media ambitions for its most dynamic offseason property, then you haven't been tracking the explosive growth of the formerly sleepy event that began in a Philadelphia hotel ballroom in 1936. It's not inconceivable the league dangles the draft as a juicy bargaining chip when negotiations begin on the next round of billion-dollar TV contracts.

The draft wasn't televised at all for its first 43 years. When fledgling ESPN asked late NFL commissioner Pete Rozelle in 1979 about airing the event, even the media-savvy Rozelle didn't see the potential. Why would anybody want to watch that, he asked.

ESPN had draft coverage all to itself for 26 years, from 1980 to 2005. Led by anchor Chris Berman, the young network did a brilliant job, turning the event into a TV juggernaut and guru Mel Kiper into a household name.

The league invited its own NFL Network cable channel to join the party in 2006. After Fox paid a hefty $3 billion for five years of Thursday Night Football, the league announced last month that Fox and NFL Network would team up to simulcast Rounds 1-3.

Pro Football Talk broke the story that the NFL would allow Fox to compete with ESPN's draft coverage. The news that a rival network was crashing ESPN's party blindsided executives in Bristol, according to SportsBusiness Journal.

The draft's TV growth is matched by its expansion on the ground. The three-day event has turned into a movable feast now that it's no longer anchored to Radio City Music Hall in New York. Cities now bid for the right to host the draft, similar to the process for the Super Bowl and the Olympics. The event generates strong revenue for host cities and the league, and it fuels rabid year-round interest.

More than 70,000 fans packed the first "outdoor" draft in Philadelphia last year, creating a rowdy and electric atmosphere. More than 100,000 fans from all 50 states registered to attend this year's draft at Jerry Jones' football palace in Arlington, Texas.

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The league will be closely researching audience results of this year's proceedings. If Fox/NFL Network's coverage draws new viewers on Fox who would not have watched the event otherwise, what's to stop the league from trying the same thing with NBC and CBS down the road?

The Fox coverage will feature Troy Aikman with NFL Network's Rich Eisen and Mike Mayock. Meanwhile, Kirk Herbstreit of "College GameDay" will succeed the departed Jon Gruden on ESPN's main desk with Kiper, host Trey Wingo and analyst Louis Riddick.

At the same time, it's possible the league could decide it wants fewer draft TV partners, not more. But the NFL has always valued the enormous reach of broadcast networks, putting the bulk of its games on free TV. After the league lost 19 percent of its TV audience over the past two seasons, spreading the draft across as many broadcast networks could make good business sense.