Horn (elbow) threw a bullpen session Friday, Chris McCosky of The Detroit News reports.
Horn underwent a left elbow scope during the offseason and is still working his way back into game shape. He's been throwing for multiple weeks and appears to be nearing game action. The left-hander pitched in 10 games out of the bullpen for Detroit last season, logging a 1.59 ERA, though his FIP was much higher at 4.37. He struck out 10 and walked seven across 11.1 innings.