Hall, 28, reached the majors last year with San Francisco, though he only worked 8 1/3 innings. He entered the year as a top-twenty organization prospect, per Baseball America, after averaging double-digit strikeout rates in his minor league career. Hall spent most of 2015 at Triple-A — his first attempt at that level — and posted a 3.46 ERA with 7.3 K/9 and 3.5 BB/9.
Arizona could allow Hall an opportunity to compete for one of its final pen slots, though perhaps the likelier scenario is that he ends up back in the minors as a depth piece. Hall was only added to the 40-man last winter, so he has options remaining.