Although it has been 20 years since WWE faced legitimate opposition from a competing sports entertainment company, a move formally announced Tuesday may have signaled the start of an in-house ratings war between its two biggest brands.

In simultaneous press releases, WWE and Fox announced Tuesday that SmackDown Live will move to the network as part of a five-year contract that begins on October 4, 2019. Not only will the brand be changing channels, it will also move from Tuesday to Friday nights. SmackDown will remain a two-hour broadcast and air live each week.

NBCUniversal has been carrying SmackDown since 2010 with it being presented on USA Network since January 2016. The company had first right of refusal to re-sign the show but declined that option when deciding to re-sign Raw to a deal reportedly three times the show's current value.

Raw has aired on USA Network for all but five years of its existence dating back to January 1993; it returned to the channel in October 2005 and will remain on the network with a new five-year deal through 2024.

The new deal between WWE and Fox is reportedly valued at $1 billion, according to The Hollywood Reporter, which called the agreement "a three-fold increase" over what WWE currently makes for SmackDown from NBCU. The outlet previously noted that WWE "had an even higher bid from a third party" that it turned down due to the massive financial and marketing commitment made by Fox.

Although SmackDown has long been seen as the "B show" in comparison to the flagship Raw, the blue brand has still averaged 2.59 million viewers per episode in 2018. Raw has averaged about three million per show over the same time period. 

One of the issues in SmackDown never reaching the level of popularity compared to Raw has been how often it has switched both nights and networks. Since its 1999 debut on UPN, the show has floated between Thursday, Friday and now Tuesday nights, including runs on The CW, MyNetwork TV and Syfy. It has aired both as a live and tape-delayed show.

In July 2016, following WWE's first brand split in five years, SmackDown moved from its tape-delayed Thursday slot to its current format of being a live show on Tuesday nights.

The likelihood for competition between brands only increases when one considers that SmackDown moves to network television on Fox, as opposed to a smaller cable home like Fox Sports 1, which was rumored to be the case had Fox been able to secure rights to both shows.

Though it has not been announced what time SmackDown Live will be broadcast on Friday nights, one should expect the window to remain 8-10 p.m. ET considering Fox's long-time programming of local news beginning at 10 p.m.

There have also been reports that WWE and Fox are working on a studio show to be broadcast on FS1 in place of "UFC Tonight," which the network will lose along with UFC programming that was acquired by ESPN.

WWE has never run one of its weekly non-syndicated TV properties on one of the "big four" broadcast networks, though it has previously aired specials, such as Saturday Night's Main Event, on NBC.