Disclaimer: The Spotlight Series will be the primary series of this blog. On any given day my goal with the series is to highlight an accomplishment that I feel is deserving of your attention as a reader. That can be as topical as a huge week from an active player or I may attempt to bring your attention to a former major leaguer whose accomplishments deserve some recognition. I may also use it as an excuse to write about teams doing something interesting as a whole. Essentially, this series is built to allow me the freedom to write about what I feel would be most interesting to the reader.

Mitch Keller had an awful, no good, very bad first taste of the majors. He finished the season sporting an ugly 7.19 ERA in 48.0 innings. There’s reason to be optimistic about the former top prospect, however, as there is significant evidence to believe that he suffered some absolutely horrendous luck in his debut.

BABIP. This is one of the first sabermetric stats that I became familiar with when I began following baseball. It stands for “Batting average on balls in play” and is essentially a way to track how much damage batters do to a pitcher when you exclude punchouts and walks. The league average for BABIP typically sits at or around .300.

Mitch Kellers’ BABIP last season was .478. How bad was that exactly? Using Baseball-reference and sorting every player to throw at least 20 innings in a season since 1950 only one player managed a worse BABIP in a single season. The player in question was Mike Burns in 2006. Mike Burns is notable for his .481 BABIP across 21 innings with two teams. The atrocious season was a death knell for the non-prospect. Fortunately, Kellers’ former status as one of the top prospects in the game will likely grant his career a stay of execution.

Now that we’ve established that Keller suffered from bad luck of historic proportions, it’s time to examine why we should be bullish on his 2020 campaign. First up is his FIP. Fielding independent pitching is a statistic used to calculate what a pitchers ERA should be. Now, some pitchers routinely under or over perform their FIP as a result of luck or defense. It’s a stat that is useful for predicting a final outcome.

Keller produced a FIP in 2019 of 3.19.

Let that sink in for a moment. Based on his FIP Keller was expected to be one of the better pitchers in baseball. Now, Fangraphs has gone to great lengths in their attempts to quantify the value of defense and has made strides in evaluating how good or bad entire teams are at playing defense. The bad news for Keller is that Fangraphs evaluated the 2019 Pirates as the worst team in baseball on the defensive side of the ball. Their defense (DEF) was rated at -51.0. That means that their team surrendered 51 more runs than a league average defensive team as a result of their own ineptitude. For the sake of comparison, the next worst team were the Orioles, who were a mere 32.5 runs below league average.

All this is to say, assuming his FIP stays exactly where it is, Keller will likely underperform it in 2020.

Next, let’s look at Kellers’ left on base percentage (LOB%). Keller had a LOB% of 59% in 2019. LOB% is a less mainstream statistic, but league average hovers around 70%, though this does fluctuate a bit more than BABIP on a season to season basis. A pitcher of average luck will only see three of every ten runners he lets on base score a run. Keller allowed four, which may not seem like much but absolutely adds up with the innings. Keller was, yet again, unlucky. There is a theme here.

Enough with the poor luck. Let’s dive into other reasons to be buying stakes in his future as an excellent starter, beginning with his arsenal.

Keller possesses as good a fastball as you’ll find in the majors. It sits at 95-96 and he threw it 59% of the time in 2019. It’s his bread and butter, and was successful in finishing at bats throughout his time in the majors.

His secondary offering is a fantastic slider. When batters swung at this pitch they whiffed roughly 47% of the time. That’s an incredible number from an incredible pitch that was somehow only thrown 19% of the time. I expect that number to rise significantly in 2020. We’ll discuss why in a moment.

His curveball sits in the low 80s and is an effective offering in its own right. He used it 17% of the time last season and that usage seems about right. Scouts have long lauded his slider as his best secondary offering, but the curveball has shown itself to be a potential plus pitch in its own right. It’s just not the double-plus pitch that the slider can be when it’s working. It does still have a great deal of use as a change of pace offering to catch a batter sitting on the slider.

Lastly, the changeup. This pitch is fine. It’s nothing special and Keller seems to know it, throwing it only 5% of the time in 2019. It’s a solid pitch if the batter isn’t expecting it, but it should be noted that scouts once considered this a potential plus pitch as well. I doubt it achieves that status in 2020, but this pitch may be worth revisiting down the road.

Why do I expect Keller to begin throwing his best pitch more often now that we’ve gone over the arsenal? Ray Searage was fired in Pittsburg. Searage used to be considered an innovative pitching coach, preaching the use of the two-seam fastball and sinker combo to induce weak contact. That strategy worked fine in 2013, 14, and 15 when the league as a whole was in the midst of the weakest offensive performances since the dead ball era. But once three true outcomes baseball became popularized many teams have moved away from the fastball approach as the two-seamer is one of the least effective pitches in the sport.

I expect new pitching coach Oscar Marin to do something Searage never seemed to grasp. I believe he’ll allow his pitchers to pitch to their strengths instead of using an organizational philosophy that became outdated nearly as quickly as it was made fashionable. If Keller is allowed to throw his secondary offerings at a 45-50% rate and relegate his fastball to the early count big things could happen.

Even without throwing his best pitch at an optimum rate he still managed to strike out 28.6% of batters faced. For reference Patrick Corbin, who had 238 strikeouts in 2019, struck hitters out at a 28.5% clip. I do not expect the Keller to match the 202 innings that Corbin threw, but 150 innings seems like an achievable target provided he begins the season in the majors (and I expect that to happen).

Alright, my case has been made for Mr. Keller. If I’m a dynasty owner trying to get an impact arm for a reduced price I’m checking the price tag on Mitch. If I had to predict a realistic stat-line for the 2020 season I could realistically view him pitching to a 3.6-7 ERA with 170k’s.

Note: All stats were sourced from Baseball-reference and fangraphs unless otherwise noted.