Arizona Diamondbacks Introduce Zack Greinke

Free agent aquisition Zack Greinke of the Arizona Diamondbacks (C) looks on with Chief Baseball Officer Tony La Russa (R) and General Manager Dave Stewart during a press conference at Chase Field on December 11, 2015 in Phoenix, Arizona.
(Dec. 11, 2015 - Source: Ralph Freso/Getty Images North America)