Show five of this year's series saw Will mistakenly hit his buzzer during an audition while, err, trying to clean it.
After doodling on the button, Will licked his thumb before rubbing it on the buzzer which quickly activated.
A startled Will quickly put on his poker face as the chair turns to reveal the singer on stage, while Sir Tom Jones couldn't contain his laughter.
Performing at the time was 25-year-old Lawrence Hill from Hertfordshire who was singing Save Tonight by Eagle Eye Cherry.
And as Will was the only coach to turn, Lawrence went straight onto the Black Eyed Peas stars' team.
"Sometimes magical things happen and and that was a magical thing," Will admitted. "I believe in destiny. He is good! We're going to make it work."
"Your coach is crazy," Jennifer Hudson remarked to Lawrence.
After his audition, Lawrence declared: "I'm going to prove to him that I deserve a place on that team."
Speaking on ITV's Good Morning Britain today, Lawrence admitted he was "horrified" on finding out what had happened.
He explained to host Susanna Reid: “I was horrified, absolutely horrified. Imagine going up for an awards ceremony after winning presenter of the year, they call your name, you go up there and they say, ‘Oh, we meant to call out Piers Morgan’s name instead.’”
However Lawrence reflected: "But at the end lot the day, it’s mission accomplished, isn’t it? I went there to do the job. I sing and write music for my job so that was like, ‘I’ve achieved what I want to achieve here, no matter what.’”
It isn't actually the first time Will has accidentally turned, doing almost the exact same thing just last year.
He told the act it was the work of a 'ghost': "So, I am sitting here listening to you sing, I am writing the notes down, and then my arm hits the button. No, but I think the Lord works in mysterious ways... I think, if there was ever like a ghost..."
In that instance, Will wasn't alone in turning and the act didn't end up on his team.
The Voice UK 2017 continues Saturdays night on ITV from 8PM.