Donald Trump loves to tell everyone to “stand proudly” for the sacred national anthem.

The president insists that’s the reason for the NFL’s supposedly sagging ratings. He claims that NFL players who protest police brutality and racial inequality during the anthem are actually protesting the anthem itself.

He referred to those same players as “sons of bitches” and demanded they be “fired” last year for not “standing proudly” during the anthem.

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So it might come as a surprise to some that during his stint as an owner in the failed United States Football League during the 1980s, Trump was not front and center standing “proudly” during the anthem. According to the new book “Football for a Buck,” Trump often spent the anthem sitting down on the phone trying to conduct business deals, berating others, or doing anything other than standing proudly.

“I’m sure sometimes Trump stood and sometimes he didn’t stand, but it’s just funny that he’s calling out all these guys for kneeling during the anthem when it was well known — and not even a big deal — that Donald Trump would sit during the anthems,” Jeff Pearlman, the book’s author, told the Daily Mail. “[He would] do work, take calls, conduct interviews. He probably never gave it a second thought.”

Philadelphia Daily News columnist Paul Domowitch also called out Trump’s Star-Spangled hypocrisy in May when he tweeted about his behavior before a 1984 playoff game in Philly.

Pearlman’s book looks at the defunct league, which lasted just three 18-game seasons from the spring of 1984 until folding in the fall of 1986. Trump, who had been repeatedly rejected in his attempts to purchase an NFL franchise, ran the New Jersey Generals.

READ MORE: Kellyanne Conway says NFL players should ‘go home’ to protest

Egged on by Trump, the financially strapped league – which was a precursor to the Arena Football League and the XFL – made the ill-fated decision to go head-to-head with the NFL in the fall of ’86 only to lose $163 million in the process.

In a last ditch effort, Trump and the rest of the league’s owners filed an antitrust lawsuit against the NFL and the USFL actually won. However, they were famously awarded just $1 in damages and the league quickly folded.