Matthew McConaughey Shares Throwback Photo Poking Fun at His Little Mr. Texas 1977 Runner-Up Title

Instagram/MatthewMcConaughey Matthew McConaughey

Matthew McConaughey is looking back on when he won Little Mr. Texas in 1977 — or so he thought.

On Monday, the actor, 51, shared a throwback photo of himself at 8 years old after participating in the competition. But in a second photo, McConaughey zoomed in on the trophy he won to show it actually said "Little Mr. Texas Runner-Up 1977."

As he elaborates on in his memoir Greenlights, McConaughey believed for decades that he won the title thanks to his mother, Kay McConaughey. It was only several years ago that he learned he actually came in second.

"For 43 years I was Little Mr Texas ... until I wasnt," McConaughey captioned his Instagram post, adding a hashtag for his memoir.

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In October, McConaughey opened up about the Little Mr. Texas competition and how he spent the next four decades living under the false pretense that he won.

"The funny thing about the story is, I was 8 years old, go to Bandera, Texas, get up on the horse, answer a few questions about mama and stuff," he said during an interview on The Kelly Clarkson Show. "And I won a trophy, that's all I remember is that I won a trophy."

But in 2018, the Dallas Buyers Club star finally learned the truth, he said.

"I was going through a file of old photographs and I found that photograph. And I was like, 'Look at me, Little Mr. Texas,' " he told host Kelly Clarkson. "And then something caught my eye. I looked on the nameplate that was engraved and I zoomed in on it and it said runner-up. So I question, I go, 'You know what, would I even be sitting here right now with the life I've had if I was raised thinking I was the runner-up?' So what did that white lie from my mom do for me, ya know?"

He added of his mom, "When she first told me I go, 'But the other guy won,' and she goes, 'No, that family had a whole bunch of money. They were too rich, they were able to buy their kid a nice suit, we couldn't afford to so they cheated.' "

Michael Buckner/Getty Images Matthew and Kay McConaughey

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McConaughey announced the release of Greenlights in July, saying at the time that the memoir is inspired by personal writings from throughout his life.

Speaking to reporters about the memoir in August, the actor said that he “went away to the desert by myself for 52 days, no electricity” to write it.

“I’ve been keeping a diary for 36 years; a couple of years ago, my wife gave me a kick in the backside to say: ‘You’ve been talking about sitting down with those for 36 years and seeing what it is for a while. Now’s the time. Get out of here.’ ”

Greenlights is now available for purchase.