Swanson signed with the Diamondbacks , receiving a $6.5 million signing bonus .
The Arizona Diamondbacks selected Swanson with the first overall selection of the 2015 Major League Baseball Draft .
Swanson signed with the Arizona Diamondbacks , receiving a $6.5 million signing bonus .
The Arizona Diamondbacks selected Swanson with the first overall selection of the 2015 Major League Baseball Draft .