Sydney Sweeney is unrecognizable as she channels famous athlete for upcoming role Fox NewsSydney Sweeney looks unrecognizable sporting boxer Christy Martin’s brown mullet for biopic New York Post Sydney Sweeney looks unrecognizable with brown mullet as boxer Christy Martin on biopic set Page SixSydney Sweeney Unrecognizable as “Female Rocky" in David Michod's Boxing Biopic Jordan RuimySee Sydney Sweeney’s Stunning Transformation For New Boxing Biopic - E!