The Pirates contingent is highlighted by Hanson, No. 41 on MLB.com's Top 100 prospects list, and Dickerson, a two-time Eastern League Player of the Week this season with Double-A Altoona.
Other Pirates prospects already assigned to Scottsdale's roster include right-handers Zach Thornton and Tyler Waldron, and infielder Gift Ngoepe.
Two more spots on the Scorpions' pitching staff are being held for pitchers in Pittsburgh's system, to be announced at a later date.
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.