Earlier this week, several outlets reported Brown had enlisted the help of Nierob, who handled Mel Gibson's case following the actor's much-publicized anti-Semitic remarks in the summer of 2006.
However, Nierob contacted Access Hollywood on Wednesday to dispel the reports he had been hired by Brown, in the wake of the singer's alleged violent incident with Rihanna.
As previously reported on AccessHollywood.com, Brown has hired public relations firm Sitrick and Company, who issued a statement on the singer's behalf earlier this week.
Sitrick and Company have advised high-profile celebrity clients, including R. Kelly, Paris Hilton, Kim Basinger, Michael Vick, Wesley Snipes and Toni Braxton.
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