Kay was promoted to High-A St. Lucie on Friday, Tim Healey of Newsday Sports reports.
Kay started 13 games for Low-A Columbia this season, logging a 4.54 ERA and 1.37 WHIP with a 78:22 K:BB across 69.1 innings. That line includes one of his best performances to date, an 11-strikeout outing over six innings against Asheville on Thursday. The left-hander will likely spend the rest of the 2018 season with St. Lucie as he continues to shine following Tommy John surgery in October of 2016.