PHOENIX -- The season is over for Phillies right-handed pitching prospect Mark Appel.
Appel, ranked No. 4 on the Phils' Top 30 Prospects list, underwent a season-ending surgery to remove a posterior bone spur in his right elbow Wednesday in Philadelphia, according to the club.
The recovery period is four to six months. Appel is expected to make a full recovery, and he should be ready for Spring Training.
With Houston, Appel went 16-11 with a 5.12 ERA in 54 appearances (53 starts) in the Minor Leagues, including a 4.48 ERA in 12 starts last season with Triple-A Fresno. He was acquired by Philadelphia on Dec. 12 in the seven-player deal that sent Ken Giles to Houston. This season, Appel went 3-3 with a 4.46 ERA in 38 1/3 innings for Triple-A Lehigh Valley, with 34 strikeouts and 20 walks.
Appel, the No. 1 pick in the 2013 Draft by the Astros, was placed on the disabled list at Triple-A with a right shoulder strain on May 27. Then, the issue with the elbow surfaced as he began his throwing progression while recovering from the shoulder injury. The club said Appel's shoulder is fine.