WASHINGTON — (CNN) Fox News has found itself in a highly unusual position: In the midst of a P.R. nightmare with no easy way out.

Donald Trump’s repeated attacks on the network — including accusations of bias — have generated foul headlines and some blatant falsehoods.

Trump is boycotting Thursday night’s GOP debate on Fox News. The move is likely to put a damper on the event’s ratings since other channels are expected to televise Trump’s competing event at 9 p.m. Eastern time.

That’s precisely what Trump wants — to hit Fox where it hurts, in the ratings race and in its advertising sales.

Trump tweeted on Wednesday night and again on Thursday morning that ad rates for the debate are falling “like a rock.”

“The ‘debate’ tonight will be a total disaster — low ratings with advertisers and advertising rates dropping like a rock,” he wrote.

There is no evidence this is true, however. Ad rates for special events like primary debates are typically set weeks and even months ahead of time. Once an advertiser makes a commitment, networks generally don’t give discounts.

A Fox News spokesperson refuted Trump’s claim in a statement on Thursday.

“The debate is completely sold out,” the network said. “No rates have changed and there are no advertisers who have backed out. Prices don’t change once the orders have been placed.”

Fox declined to say how much it is charging for 30-second ads during the debates. But because Trump has fueled record ratings, dating back to Fox’s first GOP debate last August, networks have been able to charge a premium for ad time.

Some ad packages last fall cost $200,000, according to media reports at the time.

Fox’s August debate averaged a record-smashing 25 million viewers. The channel did not expect to top that total on Thursday, even with Trump. More recent debates have generally had lower viewership; the most recent GOP debate, on NBC, had 10.2 million viewers.

But even at 10.2 million, these debates, with Trump at center stage, have been huge “hits” in TV parlance, drawing two to three times the audience for equivalent primary debates in 2008 and 2012.

Trump is well aware of that fact; he frequently brings it up during rallies and press conferences.

So his decision to forgo the debate will test just how much ratings magnetism he really has.

Thursday night’s ratings will be released by Nielsen on Friday.

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