Tyler Glasnow shows strengths, weaknesses in MLB debut as Pirates' winning streak ends

Tyler Glasnow recorded five strikeouts in his big-league debut, but he couldn't keep pace with Adam Wainwright as the Pirates fell 5-1, ending their winning streak at seven.

Glasnow's first start was decent, though far from great. He was a bit wild in the first inning, but generally avoided the walk issues that have plagued him at Triple-A this season. As expected, he leaned heavily on his fastball (which ranged from 91-97 MPH) and his curve. He breezed through the second and third innings, but struggled a bit after that, mostly because he repeatedly caught way too much of the zone with his breaking ball. A poorly placed curve on an 0-and-2 count in the fourth led to a triple by Aledmys Diaz, followed by a run on a wild pitch; another miss on a curveball in the fifth led to a Randal Grichuk solo homer.

The real damage, though, came in the sixth. Greg Garcia led off with a double (on a fastball by Glasnow, not a curve). Diaz sacrificed him over and Matt Holliday walked. Arquimedes Caminero replaced Glasnow and promptly gave up a three-run homer to Stephen Piscotty.

Overall, Glasnow struck out five, walked two and was charged with four runs over 5.2 innings. He threw 87 pitches, 54 for strikes -- which, of course, is fine. His command, however, was substandard, and if he isn't going to be walking five batters a start (which, to his credit, he didn't today -- we couldn't have taken that for granted, given his recent minor-league performances), it seems likely the focus of his work with Ray Searage will be locating his curveball.

We needn't focus on the negative, though -- Glasnow displayed his swing-and-miss stuff today, and, at least, the ability to consistently get two plus pitches into the zone. He doesn't look like an ace yet, but if you squint, you can see one coming. Glasnow also recorded his first career big-league hit today, a single in the fifth.

Anyway, as far as the outcome of the game was concerned, the Pirates didn't give themselves much of a shot, and their week-long streak came to a quiet end. Wainwright struck out nine batters over seven strong innings, and the Bucs never got close after Piscotty's homer. Notably, Andrew McCutchen's poor season continued, as he went 0-for-4 with three strikeouts.

Obviously, though, today was more important than the outcome of a single game. It marked what might turn out to be a pivotal one for the Pirates as they continue their transition from a veteran rotation to a very young one. Or maybe not -- maybe Glasnow will struggle in the weeks ahead and end up requiring more season. Both his strengths and weaknesses are clear enough that it's difficult to say how his next couple years might unfold. But today's performance did, at least provide Pirates fans with glimpses of something special.