have sent tamerlan tsarnaev down a dark path. in a boxing documentary by entertainment tonight, we hear tamerlan tsarnaev speak. eddie bishop remembers that swagger. he recalls a extremely confident tamerlan at a 2009 golden globes boxing tournament in massachusetts. what was your first impression of him when you saw him? flashy guy. you know, he had cowboy boots on, leather pants. reporter: a swagger that soon turned sour. bishop, who worked with another fighter, echoes the comments of other trainers who observed tamerlan in the ring of the great puncher, enough raw talent to have a shot at the olympic team. but i noticed he was lacking a key element. reporter: tamerlan tsarnaev, a golden gloves champion, went to the national championships in salt lake city in 2009, but fell