Single-A Tampa placed Heuer on the full-season injured list June 29 with a right elbow strain, Josh Norris of Baseball America reports.
His pro debut was delayed until April 29 due to arm soreness early in spring training, and Heuer logged 21 innings over six appearances for the Tarpons before suffering a serious elbow injury. He had a 27:14 K:BB in between arm issues, showcasing bat-missing stuff and shaky command.