Brad Paisley is well-known for his outlandish sense of humor, and he had Jimmy Fallon and the Tonight Show audience in stitches when he appeared on the show on Thursday night (Aug. 9), when he performed an unreleased ballad titled "First Cousins."

Paisley started out seriously enough, fingerpicking a slow, traditional melody from his acoustic guitar that was reminiscent of a classic country ballad.

"First date / First kiss / First taste of lovin' / You were my first ..." he sings solemnly, pausing for dramatic effect before delivering the final lyric, "cousin."

The audience burst out laughing, while Fallon grinned and covered his eyes sheepishly. Paisley managed to soldier on with a straight face, but Fallon completely loses it when Paisley starts the second verse, singing, "We got in big trouble / From your dad, and my uncle ..."

Watch the hilarious performance in the video above.

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Paisley was on the show to promote his summer tour, but he couldn't help but get in a shot at his friend Blake Shelton, whom he often kids about his drinking. Revealing that Shelton had undergone Tommy John surgery recently, he joked, "Which is that thing that pitchers get. I don't know what it was," he said, miming the gesture of repeatedly lifting a glass.

Paisley is returning to host the CMA Awards alongside Carrie Underwood for the eleventh time in 2018, and from the sound of it, we can also look for Underwood to be the target of some zingers.

"They just announced Carrie's pregnant, so there's some material right there," he told Fallon.

Paisley famously revealed the sex of Underwood's first child during the live broadcast of the CMA Awards in 2014.

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