Canadian hitmaker Michael Bublé stopped by the subway system of New York City earlier today (April 25) for an impromptu performance.

The superstar took to the Manhattan tunnels to treat morning commuters to an acapella rendition of 'Who's Lovin' You', for which he was accompanied by Naturally 7.

The track features on his brand new studio album, 'To Be Loved', which is currently the UK's No.1 record following this week's midway chart update.

Bublé, meanwhile, is expecting his first child with wife Luisana Lopilato, and recently confessed that they're having a little trouble with trying to choose names: "One of my favorite singers growing up was named Vaughn Monroe. I love Vaughn and I love Vaughn Buble, but it is out."

He added that Lopilato likes the name Marlin, but he's not convinced by it: "All I can think when you hear Marlin is fish. What I'm doing now is I'm pretty much screwing with her and I'm trying to come up with names that she thinks I'm serious about. For awhile, I've been telling her I want to name the kid Thor."