Michael Bublé Sings in NYC Subway Station for Fans

Jeremy Blacklow

Talk about bringing a smile to people's faces -- that's exactly what happened Thursday morning when Michael Bublé took to the New York City Subway for an impromptu performance of "Who's Lovin' You" with Naturally 7 off his new album "To Be Loved."

Dozens of fans gathered at the 66th Street Station on the Upper West Side when the group began their acapella rendition of the standard.

"That is the coolest thing I've ever done," the singer said. "That is when you know you've made it. Truly. Singing in the NYC subway? That is when you know you've made it."

And although it was a promotional appearance, it certainly didn't feel like work for the crooner.

"I feel like it's the most authentic, organic way to make music. You see some of the greatest musicians in the world come down here and play. Out of all the press I had to do - everything that I'm gonna do -- in Europe and in America -- this was the thing I was most excited about."

Bublé was indeed following in the footsteps of a long line of singers who have surprised New Yorkers in their underground train tunnels.

Check out Brit Jessie J back in 2011 doing her thing just as she was starting to hit big on U.S. shores:

And here's Alice Tan Ridley, the mother of Academy Award nominee Gabourey Sidibe who was a semifinalist on the fifth season of "America's Got Talent," singing "Proud Mary" in the NYC subway:

Finally, here's "American Idol" Season 6 finalist Sanjaya Malakar on "Inside Edition," singing for his supper in NYC (and, we should add, sounding better than he ever sounded on "Idol"):

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