The newbie, called "Inside Out" boasts the lyrics: "C'mon! Won't you give me something to remember/ Baby shut your mouth and turn me inside..."
But will this be her next single? Dr Luke didn't confirm anything.
"I never said inside out is the 2nd single... :-p. Maybe i'm sending brit's next single out for mix now," he Tweeted.
Brit's manager Larry Rudolph said they planned to release a second single before the album dropped, and he couldn't wait.
"We have a second song that I think we're gonna end up putting out before the album drops," he told MTV.
"I can't say with 100 percent certainty, but I think we probably will. But we're talking about it now and it is a monster. It really is."
"I don't think I've been this excited about releasing a Britney single in many, many years. It's that good. That's all I'm gonna say about it at the moment."
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