Castillo didn't ko Ruben, the bout was even in the 14th and stopped due to a bad cut over his eye. In their other two bouts Ruben won clear ud's though dropped once in both bouts. By the time Olivares fought Herrera his days of the prime rockable Ruben were at an end and some of us felt he was ready to be taken, still he got in decent shape and came close in their rematch. A few years earlier his hand would have been raised in both bouts so I can't see either of those bouts indicating how he would have done at prime bantam against Zarate.
Although Ruben Olivares may not have been the most graceful fighter in the world, I believe that he was a far more versatile fighter than Carlos Zarate, who was at sea when fighting Wilfredo Gomez. - Chuck Johnston