Mark J. Terrill/Invision/AP 1 / 9
Mark J. Terrill/Invision/AP 1 / 9

Ashton Kutcher's no king of country.

The recently separated "Two and a Half Men" star, 34, was one of the unexpected infiltrators at Sunday's Academy of Country Music Awards in Las Vegas. To present the Female Vocalist of the Year award, the star wore a ten-gallon hat and over-the-top county Western garb, and sang some excruciating bars of George Strait's "I Cross My Heart," before handing over the trophy to Miranda Lambert.

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Upon reflection, Lambert herself wasn't amused by Kutcher's shtick. The star, 28, tweeted late Monday: "Was Ashton Kutcher making fun of country or is it just me? Watching it back now and I'm kinda wondering?"

Fellow country singer Justin Moore was more direct -- and visceral. In the audience at the MGM Grand Garden Arena, he tweeted, "Seen Ashton kutcher at the acms tonight. What a douche! I don't care for people making a mockery of the way country artists' dress."

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Indeed, there was no love lost between Kutcher and most of the crowd during the show and at an afterparty, insiders reveal to Us.

"People were just like 'why is he here?' He has nothing to do with country," one attendee told Us "Nobody laughed at his dumb jokes, in fact he came off as rude. He didn't mingle."

A second source adds that Kutcher walked around the bash "with a massive posse" and "stayed in that dumb outfit for the afterparty."

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At the afterparty, Moore "was so heated over Ashton" and was "bitching about him" with Lambert's husband and show host Blake Shelton, the source says.

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