Tennessee Smokies starting pitcher, and Cubs Minor League Pitcher of the April, Tyson Miller saw his scoreless streak end at 17.2 innings last night … because he allowed a single run.

The scoreless streak ended on Miller’s first home run allowed of the season, a solo shot to start his fourth inning of work. But even with those streaks ending, Miller was still the story on the farm, as he’s been in almost every outing.

Miller earned the win in the Smokies 5-1 victory, pitching (a season-high) 7.0 innings, scattering five hits and that one earned run, with (a season-low) zero walks against three strikeouts. Believe it or not, that pesky home run caused his ERA to go up!

In seven starts this season, the 23-year-old righty has been good every time out. Miller’s season-long numbers are the stuff of video games: 38.1 IP, 20 H, 0.94 ERA, 8 BB, 33 K, 1 HR-A. He has held right-handed hitters to a .171/.210/.197 batting line, and left-handed hitters to an even-better .125/.183/.196 line. He’s inducing loads of weak contact, leading to a .192 BABIP that, while not sustainable, also speaks to his dominance.

The question now, it’s fair to ask, is when the Cubs grant Miller a promotion. Currently, the Iowa rotation looks like this: Alec Mills, Trevor Clifton, Duane Underwood Jr, Matt Swarmer, Colin Rea. Soon, after perhaps two rehab outings in A-ball, Adbert Alzolay will join. Is there room for Miller? If so, it would likely mean moving Mills and/or Underwood to the bullpen, a decision I would support.

It’s possible, even likely, that the Cubs will delay a promotion until they see how Miller handles his inevitable struggles. All the luck indicators, whether it’s that BABIP, his 2.0 HR/FB%, or a career-high 86.5 LOB%, suggest that, of course, some regression is coming (0.94 ERAs are almost definitionally not sustainable). Miller’s ability to push through those bad outings and continue to show the improvements behind this breakout will be something the Cubs player development staff looks for.

Miller has made huge strides with fastball command the last two years, and it’s leading to a career-low 5.7 BB%. He’s found himself ahead in virtually every count, where he’s able to play with a good fastball-slider tunnel, and a new pitch in his curveball.

Make no mistake, Miller is now a top 10-12 prospect in this organization, and his ceiling is no longer limited by “will he ultimately be a reliever?” talk. I mean, he hasn’t allowed more than three earned runs since August 1 last year. This is a guy who has earned a chance to make it as a starter, and, more than that, he’s loudly forcing the issue that his assigned level is not difficult enough. Great to see.