Mattaliano signed with the Orioles organization as an undrafted free agent in 2007, playing three seasons in Baltimore’s minor league system with a 3.56 ERA and 30 saves. Twenty-eight of those saves came in 2008, when he posted a 1.24 ERA and 27 saves for single-A Delmarva and saved another game for High-A Frederick.

The Pottstown, Pa. native played college baseball for Virginia Commonwealth for four years. He led VCU with a 2.64 ERA as a sophomore and was named to the CAA All-Tournament Team in 2006.