Welington Castillo's breakout campaign is getting cut a bit short.
With nine games left on the schedule, the Cubs have ruled the 26-year-old catcher out for the season with a knee injury.
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An MRI revealed a partial meniscus tear, which will require arthroscopic surgery and put Castillo on the shelf for at least four weeks.
Castillo has emerged as a piece of "The Core," alongside Starlin Castro, Anthony Rizzo, Jeff Samardzija and Travis Wood at the major-league level.
Castillo turned a major corner defensively this year, boasting a 2.8 WAR (by Baseball Reference's metric) and leads Major League Baseball with 19 DRS (defensive runs saved).
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He has also taken huge strides at the plate in the second half. After a .677 OPS prior to the All-Star break, Castillo is hitting .281/.382/.468 (.849 OPS) with six homers and 17 RBI in the second half.