In the bottom of the 10th tonight at Hagerstown, Harper hit a two-run, walk-off home run to give the Suns a 9-8 victory over Greenville, the Red Sox’ affiliate. The blast went to deep right-center field. Harper jogged around the bases without revealing much emotion, then threw his helmet in the air as he rounded third and jumped into a pile of his teammates at the plate.

The home capped another box score-stuffing night Harper. He went 4 for 5 with a walk, and for the season he is now batting .345 with 13 home runs.

Harper’s latest feat will likley add to the calls for Harper to be promoted to Class A Potomac, but early in the night Harper, 18, provided an example of why General Manager Mike Rizzo wants Harper to spend more time in Hagerstown. After hitting a single in his first at-bat, Greenville pitcher Keith Couch picked him off first after faking a throw a throw to third. After another single, Harper got caught in a rundown when he tried to advance on a passed ball.

Harper’s raw numbers – and, tonight, his clutch hitting – are an argument for him to play in Potomac. But the other aspects of Harper’s game suggest more seasoning before he reaches the next level wouldn’t hurt.