Britney Spears Sings 'Happy Birthday' Live After Slamming Lip Sync Rumors -- Watch!

Britney Spears is putting her money where her mouth is!

Days after slamming rumors that she lip syncs during her concerts, the 35-year-old singer wowed the crowed with a live rendition of "Happy Birthday."

RELATED: Britney Spears Addresses Lip Sync Accusations: 'It Really Pisses Me Off'

Spears stopped her Singapore show on June 30 to wish her bodyguard, Jacob, a happy birthday.

“I have a really special friend tonight. He’s been with me -- I’m gonna cry -- for, like, five years. He’s one of my favorite people, his name is Jacob," she told the audience. "Everyone, let’s sing 'Happy Birthday!'"

WATCH: Britney Spears Meets Fan Rocking Her Iconic 'Oops! I Did It Again' Catsuit

During an appearance on an Israeli TV show last week, Spears addressed lip sync rumors, declaring that she's "busting [her] a**" by singing live during shows. 

"A lot of people think that I don’t sing live. I usually, because I’m dancing so much, I do have a little bit of playback, but there’s a mixture of my voice and the playback," she explained. "It really pisses me off because I am busting my ass out there and singing at the same time and nobody ever really gives me credit for it, you know?"

The singer recently wrapped her tour dates in Asia. See more in the video below.