There’s quite a bit of variance among organizations with regard to how much they value and instill patience in hitters, how much they prioritize a high on-base percentage, how open they are to drafting undersized right-handed pitchers or whether they prefer skills to tools. But every organization, regardless of their prevailing philosophical stripe, covets hitters with power. It’s easy to identify power hitters at the major league level, irrespective of what measure you’re using. The traditional counting stats are grossly overvalued and rife with weaknesses, but it’s rather difficult to, say, hit 45 homers and somehow suck.
Tabbing power hitters in the early gestation periods is a bit more difficult. On the one hand, there was little doubt that Vladimir Guerrero and Alex Rodriguez, even as minor-leaguers, would one day be knocking the ever-loving crap out of the ball at the highest level. But what about Magglio Ordonez or Sammy Sosa, whose minor-league numbers hardly inspired hopes of greatness to come? What can we learn from today’s generation of power hitters?
To begin answering this question, I’ve taken the top 25 active leaders in slugging percentage (as of the end of the 2002 season) and analyzed their minor league power indicators. As always, I’ve attempted to isolate their developmental years in the minors by excluding injury-rehab assignments. Here are the minor league cumulatives for each hitter:
Name MLB SLG Mi SLG Mi ISO AB/2B Mi XBH% AB Rookie Age Abreu 0.522 0.451 0.161 21.7 32.1 2,642 23 Bagwell 0.551 0.444 0.119 14.8 27.3 710 23 Bonds 0.595 0.540 0.237 17.5 40.2 402 22 Delgado 0.554 0.515 0.214 18.4 36.1 2,354 22 Edmonds 0.524 0.437 0.142 15.3 31.0 1,511 23 Garciaparra 0.562 0.466 0.179 17.9 35.5 804 23 Giambi 0.552 0.473 0.179 12.3 39.2 913 24 Giles 0.570 0.449 0.144 22.4 26.5 2,619 25 Gonzalez, J. 0.563 0.439 0.173 20.6 34.8 2,017 20 Griffey 0.562 0.576 0.256 17.1 39.9 462 19 Guerrero 0.588 0.592 0.243 13.9 38.6 1,262 21 Helton 0.613 0.488 0.162 14.0 31.9 983 24 Jones, C. 0.544 0.487 0.174 17.7 33.0 1,679 21 Klesko 0.528 0.474 0.185 18.6 34.6 1,863 23 Martinez 0.528 0.439 0.139 15.9 30.3 2,309 26 Ordonez 0.523 0.416 0.145 16.9 33.2 2,457 23 Palmeiro 0.523 0.469 0.167 15.4 33.7 1,002 22 Piazza 0.576 0.513 0.218 15.3 40.0 1,390 25 Ramirez, M. 0.599 0.595 0.279 13.6 45.9 995 21 Rodriguez, A. 0.579 0.600 0.273 16.1 42.7 645 20 Sosa 0.546 0.401 0.136 19.9 31.5 1,751 21 Thomas 0.568 0.518 0.206 14.5 37.8 593 22 Thome 0.568 0.501 0.184 18.6 32.0 1,431 22 Vaughn, M. 0.526 0.490 0.206 17.8 37.5 1,014 23 Walker 0.575 0.498 0.225 21.8 39.7 1,524 23
A brief glossary of the statistics used…
MLB SLG – The hitter’s slugging percentage at the major league level.
Mi SLG – The hitter’s minor league slugging percentage.
Mi ISO – The hitter’s minor league isolated slugging percentage, which is simply SLG minus batting average. A minor league ISO of around 0.200 or greater generally indicates a high level of raw power.
Mi AB/2B – The hitter’s minor league ratio of at bats to doubles. Put another way,it’s the average number of at-ats between doubles for that particular hitter. It’s been theorized that hitters in the minors who hit a lot of doubles will develop additional home run power as they mature.
Mi XBH% – The hitter’s minor eague extra-base hits expressed as a percentage of total hits.
Rookie Age – The age at which the hitter reached the majors, more or less, to stay.
And here’s a composite of the 25 hitters…
Mi SLG Mi ISO AB/2B Mi XBH% AB Rookie Age 0.477 0.180 17.4 34.3 1,413 22.4
Observations…
- Jeff Bagwell showed surprisingly little raw power in the minors (0.119 ISO, the lowest of any of the 25), but he did hit doubles at a decent clip.
- If you looked only at Jason Giambi‘s SLG and ISO, you might not see a future elite power hitter, but no player in the study hit doubles at a higher rate.
- Despite being younger than their peer groups at every stop, Manny Ramirez and A-Rod still put up some devastating power numbers in the minors.
- Bobby Abreu is a rarity among power hitters in that he had more career triples than homers in the minors.
- Only three players (Guerrero, A-Rod and Ken Griffey Jr.) posted higher SLGs in the minors than in the majors.
- Only A-Rod, Manny, Mike Piazza and Barry Bonds posted an XBH% of 40.0 or greater. An indicator of future greatness?
- Only nine of 25 hitters (36 percent) posted a minor-league SLG of at least .500.
Some interesting numbers here. But to etch them in sharper relief, we’ll need to compare them to hitters who, despite some impressive minor-league power numbers, failed to wield those skills at the highest level. A good topic for next week.
Thank you for reading
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