The end of November brought another round of bad news to ESPN: the self-proclaimed Worldwide Leader in Sports lost 555,000 cable subscribers during the month, according to Nielsen. It’s a big dip in the network’s customer base that followed a record-loss of 621,000 subscribers in October.

To make things worse, the losses extended across the ESPN family. ESPN2, according to Nielsen’s estimates, lost 595,000 subscribers, and ESPNU ― its college sports-focused channel ― lost more than 700,000.

ESPN, like the broader cable industry, has been losing subscribers at a fairly regular rate ― about 300,000 per month ― over the last two years, and in a quarterly earnings report released a year ago, it admitted to losing 7 million subscribers between 2011 and 2015. So the last two months are in line with previous losses, though they have possibly accelerated ― further evidence of a shifting future for the company and, perhaps, the organizations it partners with.

Virtually all of ESPN’s competitors in the sports cable sector are seeing dips too. Chief among them, Fox Sports 1 and 2, networks that are already in fewer homes than ESPN, lost a combined 730,000 subscribers last month, according to Nielsen, and have lost nearly 2 million together since the end of September (Fox Deportes, its Spanish-language channel, lost another 750,000 in that span). This is an industry-wide issue, and it goes beyond even sports channels.

But ESPN is the face of sports broadcasting. And its loss of subscribers is potentially a bigger deal, in no small part because no network commands such a large chunk of revenue directly from subscribers. Whether they watch ESPN or not, every person who has the channel in their cable bundle pays about $7 per month for it, in addition to smaller monthly fees for ESPN2 and ESPNU.

The losses only on ESPN’s primary channel, then, could add up to about $15 million in lost subscriber revenue in the last two months alone. Given that ESPN has lost more than 10 million subscribers since it peaked at just above 100 million in 2011, its losses in direct subscriber revenue could be nearing $1 billion in annual direct revenue from subscribers.

We remain at the forefront of the industry, and no one is navigating change better than Disney and ESPN. ESPN statement

ESPN uses that money to do what it does best: secure the rights to broadcast live sporting events. In 2017, the company will shell out $7.3 billion for the right to show everything from the NFL and NBA to Wimbledon and college football. It pays $1.9 billion a year alone for its NFL package, and now commits about $1.5 billion annually for its NBA rights.

In the past, ESPN could easily afford to pay big bucks, and even overpay big bucks, for broadcast rights because of its massive subscriber base. The more that money dwindles, the less ESPN can or will pay for those rights.

ESPN pushed back against the Nielsen numbers last month, saying that they don’t reflect the company’s internal figures and don’t include its growth on alternative platforms, like PlayStation Vue, a web-based streaming service that doesn’t factor into Nielsen’s figures. It’s not wrong about the latter, though services like the relatively young Vue don’t fully account for the dip.

ESPN also rests on the fact that it is still the go-to place for sports news, talk, and live broadcasts: Ratings for everything from “First Take” to “SportsCenter” to “Monday Night Football” might be down, but they still dwarf those for most other sports programming, and game broadcasts beat pretty much anything else on television as a whole. ESPN is still America’s most-watched cable network.

It has tried to reposition itself for these sorts of changes, and is far from ringing alarm bells, at least publicly.

“We remain at the forefront of the industry,” the network said in an email statement, “and no one is navigating change better than Disney and ESPN.”

The most obvious of those navigating strategies is on digital platforms and streaming services, where ESPN is trying to reach cord-cutting, or at least package-shrinking, audiences that have transitioned to online platforms or the smaller bundles offered by services like PS Vue and Sling TV.

ESPN was the first network to bet big on sports streaming when it launched WatchESPN in 2010, and this year, Disney plunked down a 1 billion-dollar investment into BAMTech, an MLB-owned platform that the company wants to use to develop a multi-sport, subscription-based streaming service.

Those have shown both growth and promise: ESPN reached an average of 109 million viewers per month on digital platforms in the latest fiscal year, and set a monthly record of 128 million digital viewers in September.

ESPN is not a failing company by any measure, and its situation isn’t necessarily as dire as the picture Nielsen’s numbers paint.

But the longer this trend continues, the more clear it becomes that ESPN ― and, more broadly, live sports broadcasting ― is going to have to adapt fairly rapidly to larger changes in the cable landscape, especially to keep going as it has for the past four decades. What exactly that looks like isn’t totally clear, but the company obviously has its eye on the streaming market, with WatchESPN and whatever comes out of BAMTech at the forefront of those plans.

As promising as those developments might be, though, the revenue picture for streaming services is far less certain than the cash cow that is monthly cable subscription fees. One estimate pegs the monthly cost of a hypothetical Netflix-style “over-the-top” ESPN platform around $36, a fee likely too steep to reel in enough users to maintain current revenues.

That’s not just a potential issue for ESPN, or any other sports network: It also poses risks for major sports leagues too. Television rights fees are a major part of league revenues ― the NFL’s deals with Fox, ESPN, CBS and NBC could bring it $7 billion in 2016 ― and they’re only becoming more important: By 2018, the financial firm PWC estimates they’ll make up the majority of revenues for all major sports leagues.

The sports cable bubble isn’t necessarily popping yet, though changing viewing habits and lower-than-normal NFL ratings have caused at least some concern. And given how much those leagues rely on the money ESPN pays to broadcast their games, whatever changes the network makes won’t just affect sports broadcasting: They could potentially reshape the sports industry itself, too.

CORRECTION: An earlier version of this story incorrectly estimated a total number of subscribers lost by the three major ESPN channels since September.