Bill O’Reilly forecast big ratings for Monday’s first debate between Dem candidate Hillary Clinton and GOP hopeful Donald Trump, but he was much less certain what it is viewers are going to see.

Both candidates need to make their best case,” the FNC star told Jimmy Kimmel on the latter’s late-night show.

“Trump is not a policy guy,” O’Reilly said.

“What kind of a guy is he?” Kimmel wondered, which O’Reilly pronounced a good question.

“He sees himself as a master negotiator.”

Clinton, meanwhile, is far better versed in policy and, unlike Trump, knows all the players.  “If she’s smart, she’ll get right into it…and then look at him and go,  ‘Do you know what I’m talking about?’,” O’Reilly advised.

But, the former secretary of state has “a record of dubious accomplishments,” the FNC host noted, adding that’s why Monday’s debate will be “fascinating.”

Earlier in the Jimmy Kimmel Live broadcast, the host suggested different debate topics than those chosen by moderator Lester Holt.