Dayn Perry debuts his Can Of Corn column with a look at some of the greatest pitchers of this generation and how they fared in the minor leagues. Hint: not as well as you’d think.
What makes a pitching prospect? When we examine a minor leaguer from a statistical perspective, we depend upon a litany of familiar metrics and concepts–some empirically based, some articles of faith. We like pitchers with high strikeout rates, measurable success in the upper reaches of the minors, good control and strong strikeout-to-walk ratios. When we see these in tandem with sensible usage patterns and clean mechanics, we see a prospect. When we don’t, we see a pitcher whose odds of succeeding in the majors aren’t good. Right?
To test the theories cited above, we cooked up a study comprising all current pitchers who’ve spent the majority of their careers as starters and thrown, as of the end of 2002, at last 1000 innings in the majors, all while posting a career park-adjusted ERA+ (the pitcher’s ERA relative to the league average) of at least 110 (meaning an ERA at least 10 percent better than the league average). Thrown in for good measure are a handful of quality young arms who have pitched at least 500 innings and maintained a park-adjusted ERA+ of at least 120. And although the study is focused on active players, the recently retired David Cone, the putatively retired Chuck Finley and the hopefully retired Jose Rijo are in the fray as well. In order to keep the focus on the developmental years, stats compiled during rehab assignments and late-career jaunts through the minors have been excluded.
The results indicate that stellar minor league numbers leading to major league success is more exception than rule. And there’s also the staggering revelation that Al Leiter‘s first name is actually Alois.
Here are the minor-league cumulatives for all pitchers in the study (Min=minor league):
MLB Min Min Min Min Min Min
ERA+ IP K/9 BB/9 K/BB HR/9 ERA
Alvarez 112 658.2 7.4 4.1 1.8 0.6 3.32
Appier 124 401 7.4 2.7 2.7 0.2 3.12
Brown 129 302.2 5.7 3.7 1.6 0.3 4.55
Clemens 142 132.2 10.2 2.0 5.2 0.3 1.49
Colon 122 394.1 9.3 3.9 2.4 0.4 2.42
Cone 121 663.1 6.7 4.7 1.5 0.4 3.47
Fassero 112 829.2 6.6 3.7 1.8 0.6 3.59
Finley 115 41 10.5 2.9 3.7 0.2 3.51
Glavine 123 536.2 7.1 4.0 1.8 0.7 3.22
Hentgen 112 875.1 7.7 4.0 1.9 0.5 3.24
Hudson 135 268 9.0 4.3 2.1 0.5 3.22
Johnson 144 418.1 9.6 7.0 1.4 0.5 3.51
Leiter 116 692 6.9 5.5 1.3 0.3 4.15
Maddux 146 491.1 5.7 2.7 2.1 0.3 2.86
Martinez 171 517.2 8.6 3.6 2.4 0.4 3.01
Millwood 116 503 8.3 4.5 1.9 0.9 3.97
Morris 131 220 7.1 2.6 2.8 0.7 3.52
Mussina 129 178 8.2 2.1 3.9 0.6 2.43
Pettitte 118 583.2 7.2 2.6 2.8 0.3 2.51
Radke 113 569.2 7.0 2.1 3.3 0.4 3.22
Rijo 120 570.2 8.9 4.3 2.1 0.5 2.87
Schilling 127 725.1 7.1 3.2 2.3 0.5 3.34
Smoltz 122 377.1 6.0 3.8 1.6 0.7 4.13
Valdes 111 377.2 7.1 2.6 2.8 0.1 3.38
Washburn 122 640.2 7.6 3.3 2.3 0.8 4.34
Wells 111 518.2 7.5 3.6 2.1 0.5 3.80
Zito 149 170 10.0 4.2 2.4 0.4 3.18
Min Totals 12657.1 7.5 3.7 2.0 0.5 3.38
And here are the combined statistics for the entire sample group broken down by level:
Level IP ERA K/BB K/9 BB/9 HR/9 AAA 3671.67 3.71 1.89 7.23 3.83 0.56 AA 3427.67 3.48 1.94 7.25 3.74 0.59 A 4736.67 3.09 2.16 7.78 3.60 0.40 R 821.33 3.44 1.98 8.62 4.35 0.38
Some observations on the data:
- These pitchers–the best in baseball–posted an aggregate K/BB in the minors of 2.0. While that’s not bad, it’s rather underwhelming given the talent pool we’re dealing with.
- Take a semi-arbitrary successful minor league profile; say, 8.0 K/9 and 3.0 K/BB. How many here would pass muster? Only three: Roger Clemens, Mike Mussina and Chuck Finley.
- Ten of 27 pitchers (37 percent) posted career minor-league K/BB ratios of less than 2.0.
- Only three out of 27 pitchers (11.1 percent) managed 10.0 K/9 or greater for their minor league careers.
- On the positive side, almost all pitchers showed a knack for keeping the ball in the park. Is a pitcher’s minor-league HR/9 an undervalued predictive indicator?
- There wasn’t much in David Cone‘s, Kevin Brown‘s or Leiter’s files to predict the success they would go on to have.
- Brown and Greg Maddux showed little ability to strike out hitters at the minor league level.
- Clemens, on the other hand, looked bound for greatness from the start.
- Finley’s put together an impressive career despite tossing only 41 minor-league innings and having never pitched in the minors above Single-A.
- Randy Johnson‘s minor-league walk rate is positively Lalooshian.
- Ismael Valdes, despite being somewhat homer-prone in the majors, surrendered only five home runs in more than 375 minor league innings.
The level-by-level breakdowns progress as one might expect. College- and juco-trained pitchers skipped rookie ball, which accounts for the low innings total and weaker performances.
Based on this pool of pitchers, it’s clear that a record of outstanding performance in the minors is not a prerequisite for success at the highest level. This is one of those findings that raises more questions than it answers, but it’s noteworthy nonetheless. One interesting possibility is the apparent correlation between homer rate in the minors and success in the majors.
We already know of many pitchers who have laid waste to minor league hitters at every level yet went on to accomplish little in the bigs. To muddy the waters further, here are several examples of merely decent or even mediocre minor league hurlers meeting with wild success at the highest level. You know the “There Is No Such Thing As A Pitching Prospect” axiom you hear in all corners of Prospectus? Mostly, TINSTAPP refers to the tendency of young pitchers to frustrate even the most reasonable expectations. It also appears to be true on an entirely other level–some of the best major league pitchers can, and often do, come out of nowhere.
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