UPDATED with video: NBC’s The Tonight Show host Jimmy Fallon made a total mess of GOP candidate Donald Trump’s hair tonight.

In fairness, Fallon asked permission to wreak hair havoc,  first buttering up Trump, telling him his campaign has been “amazing and exciting,” and that “you say some shocking things…I can’t even believe.”

“But I’m trying not to,” Trump said, showing how diplomatic he can be.

“Can I mess your hair up?” Fallon finally got around to asking.

Trump cringed.

“I’ll be gentle,” Fallon promised.

“The people in New Hampshire, where I’m going to be in an hour or so – I hope they understand,” Trump said nobly, giving in to his fate.

Fallon stuck his hand into Trump’s tresses and gave them a very vigorous shake.

The structure shook, but did not topple, mostly falling back into place. Trump used his large hands to smooth out the mess, while Fallon politely said he would make a hash of his own hair, and proceeded to do that.

The scalp massage came at the end of a two segment interview, in which Trump told Fallon the press has become “more and more vicious” as a Trump White House gets closer and closer to reality. That includes media reports that NBC’s Commander-in-Chief Forum moderator Matt Lauer had been soft on Trump and pounded Hillary Clinton, which puts “unfair” pressure on NBC News’s upcoming debate moderator Lester Holt. He now has “got to hammer me,” Trump said, managing expectations.  Once again, Trump called for a moderator-less debate. Fallon asked how they would decide who went first, wondering if they would flip a coin, and adding, “Do you know what a coin is, by the way?… I’ll give you a coin backstage. You’ll love them.”

Fallon, who has gotten a lot of comedy mileage on Tonight with his Trump impression, told the candidate his voice has been changing across his campaign, starting at a high pitch, then “just yelling into the microphone,” and “now you’re more smoky, silky – like a Donald Trump Alec Baldwin impression type of voice.”