It may go back to AA never playing the game, but knuckleball pitchers are different breed. Their career are as unpredictable as movement of their knuckleball. You don't gamble 2 stud prospects on players like this. Tim Wakefield one of the most recent knuckleballers, had 1 big year with the Red Sox. Next 15 years of his career he was .500 pitcher with ERA of 4.75. Charlie Hough, who was one of most famous knuckleballers, was career .500 pitcher.