The 22-year-old Wallace, a third-round pick of the Rockies in 2019, debuted in low-A ball last season and pitched to a stingy 1.29 ERA/2.94 FIP with 12.43 K/9 and 3.86 BB/9 in 21 innings. Since then, Baseball America (No. 19), MLB.com (No. 20) and FanGraphs (No. 21) have placed Wallace among Colorado’s top 25 prospects. BA writes that Wallace is “the prototypical power reliever with a mid-90s fastball and a plus slider” who could quickly make his way to the majors and turn into a back-end reliever.
Wallace seems like a good return for Pillar, a pending free agent who performed decently for a non-contending Boston team before the trade. Pillar has struggled as a member of the Rockies, though, as he has batted just .255/.296/.373 in 54 plate appearances. The Rockies had designs on a playoff berth when they acquired Pillar, but they have floundered since then and now find themselves with a 22-27 record.