From my very limited experience it is who is promoting you. Obviously somebody starting from where he is at is not going to be going against the cream of fighters (if he is then he needs to change promoters). I got to watch a night of pro/amatuer boxers back in march and the pros ranged from people that had no amatuer experience to a guy that has won the Irish light weight belt this year. I spoke with one of the fighters after his bout and he said that he had no place or time to train. That he would show up when and where his promoter asked him too. He was doing it because he liked to fight and the money helped out.

The only worry I have about this Yazuraki saying he is going pro with no amatuer experience is who his promoter/manager/trainer will be putting him in the ring against. I have been watching boxing off and on for almost 20 years and have seen some guys that were pretty crappy on TV. Unfortunately its not always the best fighters that turn pro.