LeBlanc walked off the mound in the first inning of Sunday's game against Boston after experiencing elbow tightness. The injury has been diagnosed as a stress reaction.
Signed to a minor league contract in January, LeBlanc earned a big league deal in July and worked his way into the starting rotation of the rebuilding Orioles. The 36-year-old started six games, going 1-0 with an 8.06 ERA.
The Orioles were the eighth major league team LeBlanc pitched for since breaking into the big leagues in 2008 with San Diego.
Baltimore recalled lefty Keegan Akin to fill the void in the roster.
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