Pirates general manager Ben Cherington said that Barco was removed from his last start Friday at Triple-A Indianapolis due to an apparent left elbow or triceps injury, Colin Beazley of the Pittsburgh Post-Gazette reports.
Barco is scheduled to meet with Pirates team doctors Monday, at which time a formal diagnosis for his injury should be made. The 25-year-old lefty has posted a 5.46 ERA, 1.63 WHIP and 39:16 K:BB over 31.1 innings in nine appearances at Triple-A since being demoted April 29.