As you all probably know by now, Zach Stewart made his Double-A debut tonight and pitched seven shutout innings, allowing only five hits, while walking two batters and striking out eight. He also posted an eye-popping 11 GO/0 FO ratio. That's a very impressive debut. This comes after he posted a 2.32 ERA, 8 BB/32 K, and 2.42 GO/FO in 42.1 innings (seven starts) with High-A Sarasota.
I think the original plan for Stewart was to use him as a starter in order to develop his secondary stuff quicker. But after the way he's pitched in the starting role, I think the Reds have to think of him as a starter now. He has the stuff for it. According to Doug, Stewart's fastball was consistently at 91-94 and was touching 95/96. The announcer was constantly praising his slider, saying it has amazing break. Stewart also mixed in a changeup later in the game and picked up a few strikeouts with it. With two plus pitches and another pitch that is coming along nicely, I see no reason why Stewart can't handle a starting role. So far, durability doesn't seem to be a problem as he was reportedly still throwing with the same velocity late in the game tonight.
Homer Bailey and Juan Carlos Sulbaran (and Kyle Lotzkar if he can stay healthy) are probably the only pitchers in the Reds minors with top-of-rotation stuff. We may be able to add Stewart to that list if he keeps pitching like this.