Phillies pitching prospect Mark Appel underwent surgery to remove a bone spur from his right elbow, Matt Gelb of the Philadelphia Inquirer reports. He’ll miss the rest of the season, but is expected to be ready for spring training next year.
The Phillies acquired Appel, along with Vincent Velasquez, Brett Oberholtzer, Harold Arauz, and Thomas Eshelman this past offseason in the Ken Giles trade. The Astros selected him first overall in the 2013 draft.
This season with Triple-A Lehigh Valley, Appel put up a 4.46 ERA with a 34/20 K/BB ratio in 38 1/3 innings. He hadn’t started since May 22 as he was on the disabled list with a strained right shoulder. MLB Pipeline rated him the Phillies’ fourth-best prospect.