Astros rumors: Top prospect Mark Appel will be shut down soon

Appel, the top pick in July’s amateur draft, has thrown a combined 134⅓ innings between his senior year at Stanford and his first few professional starts, and Luhnow believes that the workload is starting to affect his performance:

“He didn’t say this, but he’s probably getting fatigued with the workload this year and all the intensity of being the first pick of the Draft and the expectations,” Luhnow said.

Appel, 21, has made eight starts between Houston’s Low-A and Single-A affiliates, posting a 4.50 earned-run average and nearly eight strikeouts per nine in 28 innings of work. The tall right-hander had a much more impressive 2.55 ERA going into his start on Monday, but proceeded to give up seven runs in just 3⅓ innings, increasing his ERA by nearly two full points.

The Astros had originally hoped that Appel would be able to get a few innings under his belt at Double-A before the season was out, but the right-hander will likely stay at Single-A Quad Cities for his final two starts of the year. He is scheduled to start again next Monday in Davenport, Iowa, where Luhnow will be in attendance.

Luhnow said earlier in the summer that he hadn’t ruled Appel out for a spot on the Astros’ Opening Day rotation next season. Given that Appel’s first pro stint hasn’t gone exactly as planned, it’s unclear whether that is still a possibility.

Appel hasn’t thrown more than five innings in any of his minor-league starts thus far, so he’ll likely finish the year with around 145 innings on his valuable right arm.

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