Aces Do Not Exist

If the progression of Brandon Woodruff did not awake the question last season, Corbin Burnes’s ascent through the minors has certainly raised it loud and clear, week in and week out, this season: does the Milwaukee Brewers system have an ace?

In the cases of both Woodruff and Burnes, the answer is quick and easy, “no” and “no.” Neither pitcher has the combination of raw stuff, command of that stuff, and mechanical execution that renders those 70 or 80 Overall Future Potential (OFP) grades (since OFP operates on a scale of 20 to 80, the top grade is obvious ace territory, and the 70 grade usually runs a “1/2 pitcher” description that makes that grade worth including in “ace” territory). Of course, in the case of Woodruff and Burnes, both pitchers were not even listed as Top 5 arms within the Brewers system by Baseball Prospectus entering 2017. The duo fell behind Top 10 rankers…

  • LHP Josh Hader (55-60 OFP, #3 SP or #4 SP / high leverage relief)
  • RHP Luis Ortiz (50-60 OFP, #3/#4 SP)
  • RHP Cody Ponce (45-50 OFP, average starter / late inning relief or #4/#5 SP or solid relief)

…as well as “Others of Note” RHP Devin Williams (“classic projectable righty”) and RHP Marcos Diplan (“probably future relief” but has “polish and command”). In fact, it is arguable that even with the top five arms in the system, the Brewers do not have an ace.

There is certainly an argument to be made that scouting is an imperfect science, and that perhaps the BP scouting team did not properly price Woodruff’s secondary stuff progression in Class-AA Biloxi, or that they underrated Burnes’s draft day pedigree and almost immediate professional ball impact. Yet, since the BP team bases their scouting approach upon an on-the-ground team that values actual looks, and arguably has more aggressively realistic future prospect grades than other outlets, it is difficult to see the exclusion of either Woodruff or Burnes from the 2017 Top 10 (and “Others of Note”) lists as mistakes. Similarly, accurate “useful middle to back rotation” scouting profiles might indeed “rank” lower than 15th in this Brewers system, but (more importantly) that ranking is not an insult to either player because useful MLB player should never be viewed as a slight on a prospect report.

To complicate matters, even the “accurate” ace grades do not always work out. Perhaps the best current case for this is RHP Lucas Giolito, who ranked atop the White Sox system in 2015 and landed the coveted 70 / 80 OFP (elite starting pitcher or #1/#2 starting pitcher). Giolito was a projected “ace” for many reasons:

“fastball easily works 93-97; can reach back for more; big arm-side run in lower band (93-95); explosive offering; can already throw to all four quadrants; curve shows deep two-plane break; power pitch; adept at replicating arm slot and disguise to fastball; high confidence in offering; will use at any point in the count; commands to both sides of the plate; already plus to better; elite potential; flashes feel for change; turns over with a loose wrist; displays fade with late drop; early makings of strong pitchability.”

Obviously, fans are inclined to take the good without the bad, and running with that Giolito grade also required the downsides: “Lot of body to control; can drift during landing and open early; diminishes fastball command at times; still in the early stages of building stamina; some effort in delivery wears him down; stuff can get loose and sloppy deeper into outings; velocity trails off third time through; will wrap wrist when delivering curve from time to time; change has gap to close to reach on-paper potential; loses action when throws too hard; doesn’t presently command pitch well; leaves up in zone due to early release.” Giolito was the ace in 2015, but even though he’s since dropped in rankings, the new Giolito remains a rarity in a farm system (a 60 OFP, #3 starter).

This exercise could go on and on. As far as 70 OFP aces go, recently there’s Zack Wheeler, Dylan Bundy, Taijuan Walker, Jonathan Gray, and Alex Reyes to consider. These pitchers have had their ups and for the most part remain coveted arms for nearly an organization insofar as few rotations would reject these contributors. But even with great performers like Michael Fulmer, the equation is tough; Fulmer was a 55 OFP with questions about injury and consistency that could potentially impede a #2 type starter. There is no exact science to aces, and picking one is hardly even an artform.

Even Yovani Gallardo, “an outstanding pitching prospect,” missed the ace label and was hit with “#2 and occasional All-Star” as OFP. Should 20.3 WARP signify a #2 arm, that designation would probably serve Burnes, Hader, and Woodruff quite well (and I gather Gallardo’s career earnings justify that, as well).

My standby comment to respond to Burnes / Hader / Woodruff ace talk, or the Brewers system in general, is to comment “aces do not exist.” This is not a throwaway comment, either. Aces do not exist, in the sense that from a scouting profile the grade is so rare as to basically be obsolete within the minor leagues; in the sense of performance, it is categorically true that few pitchers can be great, especially consistently so. The fun with Brew Crew Ball leader and BPMilwaukee Prospect Editor Kyle Lesniewski’s #2016BrewersAce coverage of RHP Junior Guerra is that it hit on something quite central to baseball: even in the most unorthodox historical package, Guerra emerged to dominate batters in 2016. Guerra prevented 22 runs in 2016, a feat hardly matched by a dozen arms in the NL; his splitter was one of the most effective of all time in terms of Brooks Baseball tracking, meaning that Guerra had the stuff to back up the moniker. It was both immensely fun and funny for Guerra to serve as ace, funny in the sense that the Brewers missed front rotation potential in several drafts, but landed it in the form of an age-31 rookie claimed off waivers.

In the sense that Guerra was an ace, I suspect many Brewers fans believe Burnes or Woodruff or Hader could be an ace. This is an interesting problem to discuss because it runs deep beyond semantics. It is not merely semantics to say that a “scouting ace” and a “statistical ace” are different; the difference could land the Brewers a pennant. The trouble with this determination is that it is no easier to define the dominance of a statistical ace. For example, can an ace be one-off? Could an ace have a one-and-hopefully-not-done season, perhaps like Guerra’s 2016 campaign, or does an ace require multiple (consecutive, even!) years of success in order to be termed “an ace”? But in this sense, someone like Kyle Lohse becomes an ace, which is certainly not how many fans (especially not Brewers fans) use the term; but Lohse was a fantastic pitcher from 2011-2014, posting four consecutive better than average runs prevented campaigns.

Kyle Lohse IP Runs Prevented Yovani Gallardo IP Runs Prevented
2011 188.3 3 2011 207.3 6
2012 211 24 2012 204 16
2013 198.7 16 2013 180.7 -7
2014 198.3 4 2014 192.3 2

One might call this the classic, “Is Yovani Gallardo an ace?” question. Obviously this stuff is more than semantics, because we still are inclined to talk about it in 2017. It matters to fans to say, while discussing Burnes or Hader or Woodruff, someone like Gallardo might not be an ace but was a very, very good pitcher, perhaps the next level immediately behind ace (a true #2 starter, perhaps). The table above is obviously just one captured moment in time, as it excludes 2009 and 2010 campaigns in which Gallardo was phenomenal (2.98 and 3.49 Deserved Runs Average (DRA) respectively, with 185+ IP both years) and Lohse was in transition and recovering from injuries. In either case, perhaps neither Lohse nor Gallardo are “aces” in the aspirational sense of the term, but both pitchers were among the top Senior Circuit starters for an extended period of time.


But, it’s worth chasing “aces,” and certainly a definition as such. I dove into my runs prevented data, kept annually from 2009-2011 at Sportsbubbler and Bernie’s Crew (unfortunately 2009-2010 are lost), 2012-2015 at Disciples of Uecker, and 2016 personally (officially unpublished). Analyzing a set of 845 individual pitching seasons reveals quite stunning variance that underscores the difficulty of defining acehood.

2011-2016 846 Individual Pitching Seasons
Top 10% of IP 200+ IP (or More)
Top 10% of Runs Prevented 16.0 Runs Prevented (or Better)
Median IP 99.3 IP
Median Runs Prevented -2.0 Runs Prevented
Mean IP 106.0 IP
Mean Runs Prevented -0.8 Runs Prevented
Bottom 10% of IP Lower Than 24 IP
Bottom 10% of Runs Prevented Worse Than -16.0 Runs Prevented

The big data are not thrilling; a 16 runs prevented season does not strike the “acehood” sense quite like Clayton Kershaw or Zack Greinke when they reach 50 runs prevented in a season. Yet, isolating those 85 pitching seasons above the 16 runs prevented threshold is quite interesting. Indeed, Junior Guerra was an ace in 2016, and by quite a bit (22 runs prevented being significantly better than 16); Gallardo and Lohse are definitely aces; so was Ian Kennedy, Jair Jurrjens, Dan Straily, Doug Fister, Kris Medlen, Wade Miley, Jhoulys Chacin, Henderson Alvarez, and of course Bronson Arroyo. What is striking about this list is the lack of regulars; only 20 pitchers in the 2011-2016 National League reached 16 runs prevented in two (or more) seasons:

2011-2016 Multiple 16+ Runs Prevented Seasons
Clayton Kershaw 2011 / 2012 / 2013 / 2014 / 2015 / 2016
Johnny Cueto 2011 / 2012 / 2014 / 2015 / 2016
Jake Arrieta 2014 / 2015 / 2016
Zack Greinke 2013 / 2014 / 2015
Cole Hamels 2011 / 2012 / 2014
Cliff Lee 2011 / 2012 / 2013
Jordan Zimmermann 2012 / 2013 / 2014
Madison Bumgarner 2015 / 2016
Jhoulys Chacin 2011 / 2013
Jake deGrom 2015 / 2016
Jose Fernandez 2013 / 2016
Matt Harvey 2013 / 2015
John “Clean” Lackey 2015 / 2016
Lance Lynn 2014 / 2015
Kyle Lohse 2012 / 2013
Carlos Martinez 2015 / 2016
Tanner Roark 2014 / 2016
Max Scherzer 2015 / 2016
Julio Teheran 2013 / 2016
Adam Wainwright 2013 / 2014

This, if anything, should underscore the rarity and strangeness of acehood. Madison Bumgarner has reached 16 runs prevented exactly twice, and in this definition would be exactly as much an ace as Tanner Roark. What’s intriguing about this argument is that by constructing the counterpoint that there is more to being an ace than preventing runs, such as pitching consistently throughout multiple seasons, or consistently serving as a workhorse, acehood once again becomes something that is quite murky and ill-defined. In order to argue that Tanner Roark is not an ace but Madison Bumgarner is, one is required to shift slightly away from peak performance, and search for criteria that will ultimately dissolve the definition of an ace.

Incidentially, only 20 starters in the 2011-2016 NL worked at least 200 innings more than once, although the list diverges quite a bit from the 20 runs prevented aces above. Here, again, Yovani Gallardo answers that ace question with years of consistency:

2011-2016 Multiple 200+ IP Seasons
Madison Bumgarner 2011 / 2012 / 2013 / 2014 / 2015 / 2016
Cole Hamels 2011 / 2012 / 2013 / 2014
Clayton Kershaw 2011 / 2012 / 2013 / 2015
Johnny Cueto 2012 / 2014 / 2016
Ian Kennedy 2011 / 2012 / 2014
Cliff Lee 2011 / 2012 / 2013
Bronson Arroyo 2012 / 2013
Homer Bailey 2012 / 2013
A.J. Burnett 2012 / 2014
R.A. Dickey 2011 / 2012
Yovani Gallardo 2011 / 2012
Zack Greinke 2014 / 2015
Jon Lester 2015 / 2016
Lance Lynn 2013 / 2014
Wade Miley 2013 / 2014
Jeff Samardzija 2013 / 2016
Max Scherzer 2015 / 2016
Julio Teheran 2014 / 2015
Adam Wainwright 2013 / 2014
Jordan Zimmermann 2013 / 2015

Combining innings pitched and runs prevented, one can truly see the amount of variance that is inherent in pitching performance, which should be the last nail in the coffin of “acehood” and thus (hopefully) relieve the pressure on the Brewers to develop “aces.”

2011-2016 NL Variance In Consecutive Seasons
Innings Pitched +/- 57.0 IP
Runs Prevented +/- 12.1 Runs Prevented

For this aspect of analysis, I constructed a times series involving every 2011-2016 NL pitcher who appeared during consecutive seasons in the rotational rankings (excluding “emergency starters,” who by definition only worked one start). If you’ve ever imagined that pitching performance varies a bunch on a seasonal basis…indeed it does! When faced with the criterion of working in at least two consecutive seasons from 2011-2016, 216 NL starting pitchers produced 724 pitching seasons, and their performances varied wildly on an annual basis. On a yearly basis, each pitcher might be expected to add or subtract 57 innings and add or subtract 12 runs prevented. To put this in perspective, given that 10 runs is typically understood to be worth “One Win” to an MLB club, each of these pitchers might be expected to either add or substract at least one win on average when they worked in consecutive years. 57 innings is a season’s work by a replacement starter, further demonstrating the importance of understanding variance inherent in starting pitching.

One might expect some outliers to exist, but once again, searching for “consistent” pitchers (pitchers who varied less than the average starter during consecutive seasons) piles doubt on a clear definition of “acehood.” Searching for pitchers with variance reasonably close to the +/- 12 Runs Prevented and +/- 57.0 IP marks reveals fourteen pitchers that started during consecutive years from 2011-2016 while doing so with consistent performance:

2011-2016 NL Years Variance Total Runs Prevented
Madison Bumgarner 2011-2016 3.6 to 16 IP / 3 to 16 Runs Prevented 88
Marco Estrada 2012-2014 10.3 to 22.7 IP / 2 to 12 Runs Prevented 2
Zack Greinke 2011-2014 24.6 to 48.7 IP / 5 to 13 Runs Prevented 50
Gio Gonzalez 2012-2016 1.6 to 37.0 IP / 2 to 16 Runs Prevented 38
Tim Hudson 2011-2014 36.0 to 58.0 IP / 3 to 9 Runs Prevented 11
Kyle Kendrick 2014-2015 17.0 to 56.7 IP / 3 to 5 Runs Prevented -41
Clayton Kershaw 2011-2015 5.6 to 37.7 IP / 0 (!!!) to 11 Runs Prevented 202
Tom Koehler 2013-2016 10.6 to 48.3 IP / 0 to 14 Runs Prevented -19
Mike Leake 2012-2015 11.3 to 22.3 IP / 9 to 15 Runs Prevented 16
Jeff Locke 2014-2016 35.0 to 41.0 IP / 1 to 11 Runs Prevented -41
Shelby Miller 2014-2015 9.7 to 22.3 IP / 6 to 7 Runs Prevented 15
Jon Niese 2014-2016 11.0 to 55.7 IP / 2 to 14 Runs Prevented -33
Stephen Strasburg 2013-2014 23.7 to 32.0 IP / 1 to 2 Runs Prevented 25
Ryan Vogelsong 2015-2016 49.7 to 52.7 IP / 5 to 6 Runs Prevented -25

[Really, it’s even worth arguing whether Bumgarner, Gio Gonzalez, Mike Leake, or even Tom Koehler and Jon Niese should appear on this list, because 14-to-16 runs prevented is notably higher than 12 runs prevented.]

Once again, the usual suspects are near some quite unusual arms in terms of “ace” discussions. Few would classify Jon Niese or Tom Koehler an ace; when Marco Estrada was traded to the Blue Jays, Brewers fans did not readily call him an ace when they waved goodbye (would one be happy if Burnes or Woodruff or Hader produced Estrada’s career?). However, this list should show the value of the “middle rotation” or #4/#5 scouting designation, as certainly there is room in MLB for arms like Niese, Koehler, and Estrada. Perhaps this list even casts some light on the Arizona Diamondbacks trade for Shelby Miller; maybe a pitching strapped club was not entirely shortsighted when they traded for a 15 runs prevented starter with extremely low variance between seasons (alternately, perhaps they should have looked into the other shoe dropping). Each of these points demonstrates why one should not be concerned with the ranking of the Brewers’ young prospect pitchers, and instead simply await the variance they will produce and hope for the best convergence of variance-cycles during contending seasons.

Aces do not exist. Aces do not exist in terms of scouting, where pitchers can receive ace designation as prospect and “back up” in terms of stuff, face injuries, or even hit banal developmental hurdles. Aces do not exist in terms of runs prevented, where very few arms are able to prevent runs or even work high innings pitched totals in multiple years. Finally, aces do not exist in terms of consistency, for very few National League starters demonstrated the ability to work consecutive seasons with better than average variance between 2011-2016, and many of the arms that are consistent are not “elite” performers that invoke the ideal ace. None of this should be surprising, for pitching is truly difficult, perhaps the most difficult mechanical exercise in all professional sports. This is the logical and empirical conclusion, which should drive a moral conclusion opposed to hanging “ace” tags on pitchers like Corbin Burnes, Brandon Woodruff, or Josh Hader. Each of these arms might meet one of the markers used in this article to draw ace-like comparisons at the MLB level, but the overwhelming odds are they don’t; but that alone should not be construed as a bad outcome, for there are bountiful career options without the designation of “ace.”


Photo Credit: Caylor Arnold, USAToday Sports Images

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