Subtle change helped Ackley unlock power potential in September

(Elsa/Getty)When the Yankees acquired Dustin Ackley at the trade deadline, they continued their recent trend of bringing in talented players who had fallen out of favor with their former teams. Ackley was a former tippy top prospect — Baseball America ranked him the No. 12 prospect in baseball in 2011 — who flopped, so the Yankees were able to get him for two players the Mariners have already traded elsewhere.

At worst, Ackley was going to be a more versatile Garrett Jones. Jones was the lefty hitting part-time outfielder/part-time first baseman who never played. Ackley would do the same, except add in the ability to play center field and second base, if necessary. Plus he’s seven years…