DESPITE his vein-popping rage and reality-TV theatrics, U.S. President Trump’s political rallies have become rather mundane events.

But during Thursday night’s rally in Billings, Montana, something truly unusual happened.

Standing directly behind the president during his 75-minute rant was a plaid-clad young man, at times flashing incredulous, mocking faces directly at the camera as the president incoherently blustered about his critics. That man was eventually yanked — on live TV — from his spot behind Trump.

Clips of the ordeal went viral and the plaid-clad individual became known as Plaid Shirt Guy, with outlets from Reuters to BuzzFeed reporting on it.

That viral sensation is Tyler Linfesty, 17, a Billings-area high school student who spoke with The Daily Beast on Friday via text message.

Despite what may have seemed like a concerted effort to troll the president, Linfesty said his moment in the spotlight came about entirely by chance.

“I was randomly chosen” to stand behind Trump, he said. “When people signed up to go to the rally, their names were placed into a draw and I was chosen. Because I won, I got an opportunity to meet the president.”

He shook hands with Trump during a photo opportunity, Linfesty said, and was then placed in the stands along with two friends.

At one point, during the president’s predictable soliloquy on defeating Clinton in 2016 — awkwardly claiming the electoral college is like running a mile while the popular vote, which Clinton won, is just a 100-yard dash — Linfesty was seen amusedly looking around, muttering to himself, “What?!”

Linfesty later flashed a Jim Halpert-like grin and chuckle to the camera when Trump randomly boasted of “knocking the hell out of the terrorists.” He let out a similar look of disbelief when Trump said “our country is thriving.”

And when the president claimed he’s “picked up a lot of support” in his fight against the so-called Deep State, a puzzled Linfesty raised his eyebrows and mouthed to himself, “You have?!”

But none of these reactions were planned attempts to gain attention, Linfesty said. “When he said something crazy, I thought ‘Wow that’s crazy,’ and when he said something I thought was reasonable I thought, ‘well, that’s reasonable.’”

But after enough time had passed with Linfesty’s facial reactions and lack of rapturous applause for the president, Trump’s advance team sent out a replacement, removing him from standing directly behind the president.

A woman in a black blouse approached Linfesty as Trump kept talking mere feet away in the foreground.

“I’m going to take your place now,” he recalled her saying.

“I knew that I was getting kicked out for not clapping so I didn’t fight it,” Linfesty explained.  (SD-Agencies)