The Houston Astros promoted right-handed pitching prospect Mike Foltynewicz to the big league roster on Friday. The word is that he will be used in the bullpen. Here's my current take on him.

Foltynewicz was Houston's first round pick in 2010, 19th overall, from high school in Minooka, Illinois. The Astros have had him on a textbook one-level-at-a-time development path: Low-A in '11, High-A in '12, Double-A in '13, and Triple-A in '14. His performance has been promising but erratic; he's dominant at times but will also blow up with a really bad game occasionally. This year he has a 5.08 ERA in 103 innings for Oklahoma City, with a 102/52 K/BB and 98 hits allowed.

His recent series of performances perfectly illustrate his nature as a prospect. In his last start on July 28th he struck out 10 guys in six innings, giving up three runs, three hits, and five walks. The start before that on July 21st was a disaster, with nine hits, three walks, and eight runs in four innings. The one before that on July 13th was strong: two runs in six innings, five strikeouts, one walk. The one before that was horrible: July 7th., six hits, six walks, seven runs in three innings.

Like I said, erratic.

Foltynewicz has all the fastball in the world, 93-94 with his two-seamer and up to 98 with the four-seamer. He was clocked as high as 102 last year. The four-seamer has movement as well as velocity; he doesn't throw it fast and straight. That's good in that hitters can't tee up on it even when they know its coming, but it works against him on days when his command isn't there.

His secondary pitches are as inconsistent as his command. His curveball and slider can range between plus and poor, depending on what day you see him. The change-up is similar, ranging from very good to weak.

On his best days, when his secondary pitches are working and his command is in gear, he looks like a future number two starter. On his bad days, when he can't throw strikes or when his off-speed stuff is vacationing, he looks more like a reliever, albeit one with closer potential.

I really like Foltynewicz's upside and it will be interesting to see how he adapts to the majors. He's done a good job staying healthy and I have not given up on the idea that he can be a starter in the medium and long runs, but a relief apprenticeship seems wise. I think bullpen use makes sense at this point; letting him get his feet wet in limited looks, preparing for a larger role as a starter or possible closer in the future.

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