The Voice coach was getting his own back on the late night talk show host for making him try sushi for the first time during a previous sketch, so he thought what better way than to take his friend down to the farm.
Shelton, 40, kicked off the humor by mocking his buddy’s ridiculous attire.
“You dressed very disrespectful, you look like Howdy Doody right now,” he joked of Fallon’s overalls and straw hat combo. “You think this is a game? This is serious!”
Both men struggled to keep a straight face as Shelton explained how Fallon, 42, was about to touch Oreo the cow in “her very private area."
But when the novice reached under the animal before the Oklahoma-raised singer had finished giving him directions he yelled: “You don’t just reach out and grab a teat. This is all about romance and finesse. So have a connection with Oreo.”
The conversation took an inappropriate turn as they discussed the proper hand motions when milking the udders.
Shelton insisted: “You don’t stroke it ... it’s more of a squeeze” and accompanied his explanation with some interesting hand motions.
Once the tutorial was over, Fallon reached for a bowl of cereal and attempted to squirt some fresh milk directly onto his breakfast.
He had no luck though, and Shelton had to get his hands dirty to show him exactly how it was done.
Together they managed to eventually fill enough for a couple of shot glasses, and Shelton said it was tradition to throw back a glass of your first milk.
As Fallon gagged on the warm, fresh beverage Shelton cheekily threw his over his shoulder.
Check out the hilarious video above.
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