Call it a comeback. Not just by the Kansas City Royals, which forced a seventh and deciding game for the World Series Wednesday night, but also for the Fox Broadcasting Network, which was facing what could be the lowest-rated series in TV history.

Going into the Series, Fox and Major League Baseball faced their worst nightmare: a small-market team playing San Francisco, the No. 6 U.S. media market, where one was expected to dominate, raising the ugly specter of a low-rated sweep.

The Series got off to an inauspicious start. The opener was the lowest-rated in the history of the Fall Classic, with 12.7 million viewers. The next four games didn’t get much better from a ratings perspective. Most were blowouts that failed to hold viewer interest. Sunday’s Game 5 was defeated in the ratings by not only NBC's "Sunday Night Football," but also by AMC’s “Walking Dead.” Going into Game 6, it was the lowest-rated World Series in TV history, averaging just 12.1 million viewers a night.

“One of the problems is that besides the fact this is not a marquee matchup is that a lot of the games have been blowouts," said Brad Adgate, research director at Horizon Media. "I don’t think that’s helped it at all.”

But the Royals’ 10-0 drubbing of the Giants on Tuesday night brought a big sigh of relief at Fox and the league by extending the World Series to a seventh game. A Game 7 means 75 percent more ad spots to sell than a four-game sweep, and those are selling at $520,000 per 30-second spot.

“It’s great to have a seventh game of the World Series for only the second time since 2002,” said Fox Sports spokesman Lou D’Ermilio, with no small understatement. Kantar Media estimates that Fox rakes in $43 million in ad dollars for each game played.

Even better: Now Fox gets a Game 7 on Wednesday night with no competition from the NFL. "The NFL continues to drive massive ratings and its fortunate for Fox they don't have to worry about competing with them tonight," said David Carter, director of the Sports Business Institute at USC's Marshall School of Business.

What's more is Game 7's typically draw large audiences. The last Game 7 between Texas Rangers and St. Louis Cardinals brought in 25.4 million viewers in 2011; 2002’s Game 7 between the Anaheim Angels and Giants brought in 30.8 million viewers. If the pattern holds, Game 7 should raise the overall average and give nice upside for Fox, which is in the first year of an eight-year deal with MLB worth $800 million a year (a fee it is splitting with Turner Broadcasting).




"This could easily do over 20 million viewers," Adgate said. Fox has to pull the numbers above 12.7 million for the 2012 matchup between the Giants and Rangers to avoid setting a new low.

Ad spots aren’t sold for games five through seven until there is certainty that those games will be played. Once the games open up MLB sponsors get first dibs; after that it’s first-come, first-served. A source close to Fox said all spots were snapped up by existing advertisers.

But even with smaller audiences, live sports remain in-demand by TV advertisers because they are more likely to be watched live, and not recorded on DVRs, where the ads are mostly skipped.

"From a financial perspective Fox is happy," Adgate said. "Its not Dodgers - Yankees but this is the next best thing."