When Anthony DeSclafani arrived at Spring Training last February, he was one of a handful of young pitchers competing for a spot in the back end of the Reds' rotation. Now, a year later, the 25-year-old is Cincinnati's presumed Opening Day starter.

This owes more to the changing state of the Reds than to a change in DeSclafani himself; a year ago, Cincinnati had yet to firmly establish itself as a team dedicated to rebuilding. Johnny Cueto and Mike Leake were still aboard, Homer Bailey wasn't an injury-struck question mark, and the rotation hadn't become an experiment of placing faith in rookies.

Without this shift in the team's intentions and the accompanying quirks of circumstance, DeSclafani likely wouldn't be poised to enter 2016 as the Reds' staff ace. But to attribute his ascent solely to the team's situation would be unfair, as DeSclafani showed notable improvement over the course of last season—though you wouldn't know it if you weren't looking for it.

In a radio broadcast of a Reds spring game this week, it was mentioned offhand that DeSclafani had struggled towards the end of the season. It makes sense that a cursory glance at some basic figures would lead you to that conclusion. Six of his last eight decisions were losses. A 3.65 ERA in the first half of the season rose to 4.52 in the second, and his opponent slash line increased from .247/.326/.383 to .291/.330/.451.

Thankfully we don't have to rely on a cursory glance at some basic figures, so we can tell that DeSclafani's second half was not significantly worse than his first. In fact, it was significantly better—albeit hidden behind some unfortunate luck.

While DeSclafani's first half of the season was solid enough for a rookie pitcher, his strikeout and walk percentages were not particularly encouraging. He arrived at the All-Star break with a 1.80 K/BB ratio, putting him near the bottom of the MLB leaderboard (91st out of 97 qualified pitchers).

In the second half, however, that changed dramatically. DeSclafani's control showed impressive improvement, as he cut his walk rate nearly in half, and his strikeout rate increased. The result was a K/BB ratio of 5.50, good enough to more or less invert his standing on that leaderboard—landing in the top 10 for the season's second half.

What started going right for DeSclafani in the second half? In large part, his curveball, which Shawn Brody analyzed right here on Beyond the Box Score in September. DeSclafani used the pitch only sparingly before last June, but he began working it in more as the summer wore on, and the results were encouraging. By September, the curveball was generating whiffs on half of all swings.

So, then, what started going wrong for DeSclafani in the second half? If he upgraded his command, increased his strikeouts, and introduced the curve to much more success—what was behind the inflated ERA, improved opponent performance, and that radio assessment of a discouraging second half?

In all likelihood, not anything to worry about (as you might expect, given the types of stats you need to use to say that DeSclafani's second half was worse compared to the types of stats you need to say that it was better). A look at some of his peripherals shows a fairly clear culprit.

K/9 BB/9 K/BB (MLB rank) BABIP HR/FB 1st Half 6.59 3.65 1.80 (91st) .289 6.6% 2nd Half 8.28 1.51 5.50 (10th) .354 12.3%%

It's hard to look good when your opponents are putting up a BABIP over .350 and that many fly balls are turning into home runs. These are areas that are notoriously dominated by luck—not entirely out of a pitcher's control, but far enough from it to be fickle and frustrating. Now, since 2015 was DeSclafani's first full year in the majors, he doesn't have any reliable baseline figures to compare these to, and it's possible that he's someone who performs worse than average in these areas. But it's very unlikely that he's this much worse than average. These changes weren't accompanied by any significant differences in the rest of his batted ball profile or the type of contact hitters were making against him, so there's no reason to believe that there's anything more discouraging at work here—just a half season of bothersome, garden-variety bad luck.

But that bad luck didn't disguise the parts of DeSclafani's second half that matter heading into 2016. While the BABIP will likely return to something closer to normal, there's a very real chance that the changes he can control (the strikeouts and walks) are here to stay. No matter what numbers you're using, DeSclafani's 2015 was a tale of two halves—but only one set of those halves offers something significant for 2016.

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Emma Baccellieri is a contributor to Beyond the Box Score. You can follow her on Twitter at @emmabaccellieri.