Ciriaco, a speedy infield prospect, hit .296 and stole 38 bases in 121 games with Double-A Mobile in 2009.
Valdez started 18 games for Triple-A Reno in 2009, striking out 60 batters in 96 innings.
Roemer, a first-round selection of the D-backs in 2007 First-Year Player Draft, started 22 games for Mobile last season, going 9-9 with a 4.28 ERA. Torra is also a former first-rounder, going in the 2005 Draft. Torra compiled a 3.75 ERA in 180 innings of work for Mobile, striking out 116 batters.
After being called up to Reno, Schmidt continued to impress in 2009, tallying seven hits in 16 at-bats to go with a strong season at Class A Advanced Visalia.
Currently the D-backs' Major League camp consists of 23 pitchers, five catchers, 11 infielders, and seven outfielders -- a total of 46 players.
Bailey Stephens is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.