Astros breakout candidate: Brett Oberholtzer

Back in late 2013, the baseball brain trust found in the comments sections of internet message boards directed a lot of their attention and opinions towards deciding the eventual makeup of the Houston Astros' 2014 starting pitching rotation.  The club had just come off a season in which they posted the lowest team pitching WAR, the highest ERA, and the highest FIP in all of baseball.  For those less statistically inclined, I apologize in advance for the rest of this article, but the takeaway is this: the 2013 Astros were really, really, really bad at pitching.

A common theme among discussions about the 2014 rotation was that one Dallas Keuchel had no place in it, per a majority of commenters and club beat writers, prompting a humorous dig by Keuchel himself that he wasn't included in a list of potentials.  Many, if not most, fans had Keuchel pegged for a long relief role or back to AAA.

Then he posted a 2.93 ERA over 200 innings, and was in brief but valid mentions as a possible Cy Young award candidate.

There were statistical indicators in 2013 that his past performance was due for some positive correction, as well as the typical, "hey this guy needs to adjust to the major leagues" comments from those who supported him.  In hindsight, those folks were right.

But this article is about 2014's rookie pitcher Brett Oberholtzer and whether or not he can expect a breakout as he heads into his true sophomore season.  (Well, not really a rookie, since he pitched 71 innings in 2013, but with only 215 MLB innings under his belt and at age 25, calling 2015 his sophomore season is completely defensible.)

Oberholtzer is working his way back from a hand blister that had him start the season on DL, and there are indicators that once he shakes off the rust, he should have a nice season, if not exactly Keuchel-esque.  Oberholtzer was acquired in 2011 in the unfairly-infamous trade that sent center fielder Michael Bourn to the Atlanta Braves.  While the other players acquired in that trade promptly failed to do anything noteworthy except break their pinky finger in a tough-guy fashion and pick fights with former teammates and get busted for peanut butter-laced marijuana, Oberholtzer has already accumulated 3.5 WAR in his 215 innings as a Houston Astros pitcher.  To put that into context, Julio Teheran posted a 3.5 WAR for the Braves last season in 221 innings, and Ian Kennedy and Lance Lynn were in the same ballpark, although in fewer IP.  Oberholtzer's 4.39 ERA aside (not bad for a 24-year-old "rookie"), the metrics that comprise the WAR calculation thought quite highly of Oberholtzer last season

Oberholtzer's batted ball tendencies

Hat tip to TCB reader reillocity for some of the tidbits that I'm including here.  Some of his evidence improved my already strong confidence that most fans are underrating Oberholtzer's potential.

Over the past decade, the development and trumpeting of ground ball pitchers has been so en vogue that it has even prompted some teams to construct their lineups to combat and exploit teams' love of worm burning pitchers such as Keuchel and Chad Qualls.  Even still, the average fan goes along with the media and manager-speak fueled narrative that FLY BALLS ARE BAD, MMKAY?  The theory is that home runs are fly balls, and so fly balls are bad.  But not all rectangles are square, and that's where Oberholtzer comes in.

Many pitchers are successful with high flyball rates.  The ranks of fly ball pitchers include illustrious names like Scherzer, Peavy, Darvish, Sale, Verlander, Weaver (the one with the hair), and Teheran.  Some of these guys have ground ball rates that are almost half of Keuchel's.  Among the highest reaches of the FB% leaderboard sits Oberholtzer.  At a 42.5% fly ball rate, he ranks 10th among the 107 starting pitchers who threw at least 140 innings last season.

If one can shed the Fly Ball to Home Run correlation that exists in one's mind erroneously and think about fly balls for a second, one realizes that Fly Balls are typically easier to field than ground balls.  Fly balls don't take weird bounces in the dirt.  They aren't dependent on more than one player receiving, throwing, then receiving the ball again.  The ball goes in the air.  The fielder has more time to position himself underneath.  And a catch is an out, without an additional game of catch with another player.  And so, a pitcher who can induce weak fly ball contact is a valuable asset indeed.

Data backs this up.  Yes, ground balls are typically good for a pitcher.  But so are non-pull fly balls.  Fly balls to center field provided a 0.01 run expectancy value over the sample studied, identical to a ground ball to the opposite field.  But flies to the opposite field produce a -0.11 run expectancy, nearly identical to ground balls up the middle, and actually better than pull-side ground balls.  Whodathunkit?

With that in mind, look at Oberholtzer's (a lefty) batted ball chart against right-handed batters:

Source: FanGraphs

Approximately 75% of Oberholtzer's fly balls to right-handers are to the opposite field, where they die a pitiful death in George Springer's glove.  Only one of those oppo-field fly balls went for a home run.  A large number of his other batted balls are pull-side ground balls, also yielding a negative run expectancy of nearly equivalent value.  Versus left-handed hitters, his batted balls still seem to favor this opposite-field fly ball / pull-side ground ball tendency.

Source: FanGraphs

From this, one can conclude that Oberholtzer has a real skill that has tangible value in preventing runs, one that, if he can maintain his fly ball rate, is not only repeatable, but can set him above a large number of his peers.

How to interpret FIP and xFIP on the extremes

One of the indicators of Dallas Keuchel's breakout after 2013 was the 1-1/2 run difference between his ERA and his xFIP.  FIP and xFIP use strikeouts, walks, HBP, and HR as proxies to calculate what a pitcher's ERA would be if only things that he could control were accounted for, instead of annoying things like team defense, bad luck, and intestinal parasites.  Keuchel's HR/FB rate was a sky-high 17.4%, which is high even for a ground ball pitcher, who usually maintain a rate higher than the league-average of 10%-ish.  xFIP accounts for fluctuations in HR/FB rate (compared to FIP) by using the league-average HR/FB rate in its calculation instead of straight count of home runs allowed.

For an extreme ground ball pitcher, this means that the effect of his HR/FB rate is inflated by FIP, as Keuchel's was., and so xFIP is probably a better indicator of true talent and future performance than FIP.  Thus, when Keuchel maintained a 9.6% HR/FB rate in 2014, his ERA and FIP were clsoer to his 2013 xFIP than his ERA was in 2013.

Extreme fly ball pitchers like Oberholtzer are exactly the opposite.  Fly ball pitchers who induce weak contact are able to maintain a lower-than-average HR/FB rate compared to the rest of the league.  As evidence, of the top 20 fly ball pitchers last season, only Hector Noesi and Dan Haren "boasted" HR/FB rates meaningfully higher than the MLB average of 9.5%  Some, such as Justin Verlander and Phil Hughes, were able to sustain ridiculously low rates, under 7%.  For his career so far, Oberholtzer's HR/FB rate sits at 6.2%, very close to Hughes' 2014 rate, and his tendency to create repeatable weak contact (per the graphs above) seem to indicate that he can maintain a very low HR/FB rate.

This would lead to accepting Oberholtzer's FIP as a truer measure of his true talent and indiciator of future performance, rather than his xFIP.  xFIP would be artificially inflated by boosting his HR/FB well above a rate that he can sustain.  This can be taken as hopeful by Astros fans, since his 2014 FIP, at 3.56, was almost a full run lower than his ERA.  Even his xFIP was lower than his ERA, which is extremely hopeful, and indicates that his .325 BABIP was probably inflated beyond where it should be.

Summary

Based on the reasons cited above, Astros fans who pay attention to underlying statistics have every reason to believe that Oberholtzer will improve noticeably from his 2014 ERA.  Fans who don't dig the numbers will likely be surprised by a pitcher who, like Keuchel in 2013, they think is a AAA pitcher, long reliever, or even a throw-in to be tossed aside in off-season trade scenarios.

If healthy, indications from Oberholtzer's impressive but unheralded 2014 season suggest that he will chop a hefty chunk off of his ERA moving forward.  And if one wants to include growth and maturity as a major leaguer (remember, he's only 25 years old, the youngest starting pitcher on the roster, even younger than rookie Asher Wojciechowski), then there's even more room for optimism beyond what the stats imply.

CRPerry13's bold prediction for Brett Oberholtzer's 2015:

170 IP, 3.50 ERA, 1.90 BB/9, 6.00 K/9, 10+ wins