It’s pretty obvious that Donald Trumplikes golf, but he may like cheating at it even more.

That’s according to sports writer Rick Reilly, author of a new book about Trump’s golf game, Commander In Cheat: How Golf Explains Trump.

Reilly, who claims the president goes to ridiculous lengths to ensure he wins each match, appeared on “Morning Joe” Tuesday and said he’d learned how Trump won the 18 club championships he repeatedly boasts about.

“He said when he buys a new course, he plays the first round by himself and calls that the club championship,” Reilly said. “So I started calling around, people said, ’Yeah, one day he was at Trump Philly, and we played the club championship at Trump Bedminster, and he called and said, ‘Who won the championship?’ They said ‘Joe Shmoe’ shot 76, Trump goes, ‘I shot 73 up here at Trump Philly, make me the champion.’”

Reilly said that not only did Trump make himself the champion at each one of his golf courses, but he used those phony titles as proof of his presidential qualifications.

“When he started campaigning on this as ‘I’m a winner, I can close out, I’ve won 18 club championships, and that’s against the best players,’ that bothered me,” Reilly said. “I don’t know anything about politics — you guys know about politics — but I know about golf. You don’t get to do that.”

Reilly was still teed off about Trump’s cheating when he appeared on CNN.

“He cheats like a mafia accountant. He cheats crazy. He cheats whether you’re watching or not. He cheats whether you like it or not,” Reilly said. “He kicks the ball out of the rough so many times the caddies call him Pelé.”

Reilly said Trump is so bent on winning that he even cheats when playing against people who are objectively better golfers, like Tiger Woods.

During a 2017 round with Woods, Trump reportedly didn’t account for two balls he hit into the water on one hole, according to The Associated Press, citing one of his playing partners.

“In golf, he’s definitely not exonerated,” Reilly told the AP. “There’s been dozens and dozens of people that can declare him guilty of cheating.”

So far, Trump hasn’t commented on the book, but a former Sports Illustrated managing editor who played with him said he once justified cheating by saying “the guys I play with cheat all the time.”

Still, Reilly says he’s prepared if the president goes on a Twitter tirade about the book.

“When Trump hates it or whatever, I’m going to be like, ‘Alright, who read it to you?’” he told The Ringer.