Sam Smith has a potent message for the man who broke his heart and inspired debut album In the Lonely Hour.

The singer won four Grammy Awards on Sunday night, including Song of the Year and Best New Artist, and made a point of thanking the person who made it happen.

"This is the best night of my life," the 22-year-old said as he won Record of the Year. "Just a quick one — I want to thank the man who this record is about, who I fell in love with last year. Thank you so much for breaking my heart because you got me four Grammys!"

Sam also won in the Best Pop Vocal Album category, and was clearly overwhelmed with emotion as the night progressed.

"I just want to say that before I made this record, I was doing everything to try to get my music heard," he said. "I tried to lose weight and I was making awful music. It was only until I started to be myself that the music flowed and the people started to listen."

Bless! Sam talked more backstage about the mystery heartbreaker, making it seem as if they are still on somewhat good terms.

"I haven't had time [to call him] because I'm here," he said in the pressroom. "I'll be seeing him soon so I can let him touch the Grammys once!" He added: "'Stay With Me' is a very simple song in terms of melody, but in terms of lyrics it's not. I really feel like that's the thing that is connected."

Erm, pretty sure he was watching, Sam. If he says he wasn't he's lying!