Britney Spears' shelved pop comeback has been given a boost by producer Sean Garrett, who insists the Toxic singer's next single is "out of control." A week after her publicist revealed record executives had pushed Spears' comeback album back to 2008 - prompting reports early studio work was no good - Garrett, who has just completed sessions with Spears, insists the singer has created another pop masterpiece. He tells, "I've got this one record I've been holding for 10 months that everyone has tried to buy, but I stayed with Britney on it. I guarantee it will shake up the world. "It's uptempo, out of control... It's wowzers, produced by me and Bloodshy. I can't give the title yet, but the record is done and definitely what people want to hear from her." And Garrett knows what he's talking about - he shared the Songwriter of The Year honour at the BMI Awards in May (07).