The organization is also expected to make the signings of Tom Gordon and Paul Quantrill official within the next few days.
Sierra, 21, went 3-5 with a 2.09 ERA in 51 games last season with the Athletics Class-A Midwest League Affiliate, the Kane County Cougars. Edwardo was signed by the A's out of the Dominican Republic when he was 16 in 1999 and his fastball can reach the mid-nineties, but needs to improve on his breaking pitches.
Stotts, 23, began the season with Class-A Modest, hitting .284 with 2 homers, 37 RBIs, and 11 stolen bases, but was promoted to Double-A. There he shined, finishing with a .307 average and 14 RBIs in 176 ABs. J.T. has the potential to be a very good defensive player, is patient at the plate, and uses his speed very well.
Information from The Associated Press was used in this report.