R&B singer / actor Usher confirmed on Thursday that he has signed on to portray legendary boxer Sugar Ray Leonard in a upcoming biopic film titled "Hands of Stone."  The singer has reportedly been in London finishing up work on his next album, and told the BBC that he has also been training for the film, which is actually based on the life of Roberto Duran.  Acting great Robert DeNiro has also been cast in the film, and will portray Duran's longtime trainer Ray Arcell, while Duran himself will be played by actor Gael Bernal.