At what moment should a boxer say the risk is too great? Has Tim Tszyu reached that threshold? The 30-year-old has been famed for his refusal to yield across his career, so it was telling that he could not rise from his corner as he handed victory to Sebastian Fundora in Las Vegas. Is this the end of the road? We ask Simon Smale to make a case for and against retirement. Featured: Simon Smale, boxing journalist, ABC Sport.