Disney, Fox and Warner Bros. Join Forces for Sports Streaming Service

Sports and live events, like award shows, have long been seen as a bulwark against cord cutting. Rich Greenfield, a media analyst at LightShed Partners, said in an interview that he was encouraged by the new service, which is likely to satisfy some sports viewers who are fed up with paying for traditional TV channels they don’t want. But he said the absence of companies like Paramount meant that die-hard fans still wouldn’t have access to a complete array of live sports.

“It’s a step in the right direction,” Mr. Greenfield said. “The question is: Is it enough?”

In some ways, this bundle of channels is an evolution, not a revolution. The companies already sell their channels to traditional cable distributors like Comcast and Charter, and to digital distributors, like Sling and YouTube TV. The new service is essentially just another distributor to sell channels to, though the companies collectively own it and the grouping of channels being offered to subscribers is novel.

Sports fans will find games and matches from almost every major league on the app. In addition to National Football League and National Basketball Association games, the service will offer action from Major League Baseball, the National Hockey League, the PGA Tour, Grand Slam tennis, professional soccer, major college conferences and the Ultimate Fighting Championship.

Network contracts with leagues are usually specific about where games can be shown, and most leagues have been hesitant about allowing too many games to move off broadcast and cable channels and making a full transition to streaming. By structuring the new app in such a way that everything on the channels — sports and nonsports content alike — is available to subscribers, the companies did not need to secure permission from the leagues for the games.

While this service goes a long way toward allowing sports fans to watch a significant number of games in a single app, it does not bundle all sports together. NBC, CBS and Amazon, in particular, have major rights — like many N.F.L. games, major golf tournaments and the Olympics — that will not be a part of the service. Regional sports networks, where most fans still watch their local baseball, basketball and hockey teams, are also not included.