Why Are the Greatest the Greatest?

Dave Paisley

When evaluating baseball talent, the true measure of greatness is that set by the legends of the past. As the great players of today are in various stages of their careers, I thought it would be interesting to have a baseline of career progression based on the all-time top performers.

First, I decided to take a look at the top ten career sluggers of all time and see how they performed over the course of their careers. While I chose the top ten players based on slugging average, I chose to evaluate their performance by using on-base percentage plus slugging average (OPS).

While there are much more complex evaluators of performance, such as Bill James' Runs Created, OPS combines simplicity and ease in determining raw performance. Both on-base percentage and slugging average are readily available in most statistical publications now, and anyone who can add two three-digit numbers can have the inside track on evaluating baseball talent.

At the severe risk of sounding simplistic, the ultimate aim of baseball is to win games, and wins are manufactured by scoring more runs than the opposition. Runs, in turn, are manufactured from the bases that runners advance from the raw material of walks and hits. At each successive level there is less luck involved. Hits and walks are a contest of skill between pitcher and batter, and while there is always some luck involved, it is the most basic level of competition in the game.

I like to think of a run scored as having two elements to it - the runner that scores the run, and the batter that drives it in. Both are equally important, so each contributor should be credited with half a run generated. Of course, on a home run, the batter gets credit for both halves. On-base percentage measures the ability of a batter to get on base, and is reflected more in runs scored than batted in. Slugging average measures the productivity of a batter in generating multiple-base hits, and is reflected more in runs batted in than runs scored. The combination of the two very accurately reflects a player's ability to generate runs.

Scoring runs involves a little more luck than just getting the hits and walks, as it relies on bunching them together in sufficient quantity to get one or more runners around to home plate. Winning games is an even chancier proposition, as it involves scoring more runs than the opposition, where the number of the opponent's runs is yet another variable in the equation.

So, if runs are generated from hits and walks, then OPS is the simplest and most readily available statistic that combines hits, walks and extra bases. It has the statistical elegance of also having an even 1.000 as a hallmark of excellence. Any player with an on-base percentage of .400 and a slugging average of .600 is performing in the top levels of the game.

So what does OPS look like over the career of the top performers of history? Who are these top performers? It shouldn't surprise you that the top player in the history of the game is Babe Ruth, with a career OPS of 1.164. The remainder of the top ten sluggers are Ted Williams, Lou Gehrig, Jimmie Foxx, Hank Greenberg, Joe DiMaggio, Rogers Hornsby, Johnny Mize, Stan Musial and Willie Mays. I took their career OPS numbers by year, averaged and smoothed them, and graphed them out as follows...

While offensive levels have waxed and waned over the decades, and we can make adjustments for that, I prefer to deal with the numbers as they exist, keeping in mind the fact that some players are helped and others hindered by the era in which they played. That said, those adjustments are not so great that an apparently terrible player was actually really great, or a great player actually terrible. Ruth and Gehrig played together in one of the most offense-oriented eras in baseball, but no era adjustment will ever tarnish their achievements.

Current league average OPS is around .750, and it's interesting to see that the best players in history start off above that level even at age 20. A steady progression through their early twenties results in a peak at age 27. We could characterize up to age 26 as the "development" phase. After reaching that peak level, they maintain it till about age 32. We'll characterize this period as the "peak" of their careers. After age 32, there is a steady decline, but note that even until age 42 (for those that did hang on that long), these players are still above average. The early part of the later years, up to age 36, could be called the "sunset" years, and the even later years as the "twilight" of their careers.

It was fascinating to me that this pattern emerged quite clearly from only ten players, especially when it includes Ted Williams, who missed four years to the war and had some monster years in his mid-thirties.

After seeing the career progression of these great players, I wondered how quickly performance drops off to the next best group of ten. This next group includes Mickey Mantle, Hank Aaron, Ralph Kiner, Hack Wilson, Chuck Klein, Duke Snider and Frank Robinson. Although there are several active players in this range, I've eliminated them from the list for now. The curve for this next rank is markedly below the top 10, by about 100 points of OPS. The curves are closer together in the early years and diverge slightly with age, so the differential at age 40 is about 150 points.

I suspect if took subsequent groups of 10, the lines would be closer and closer as i worked down the list, but that's an exercise for another day.

So that's a brief look at the career progression of a bunch of Hall-of-Famers. Another caveat about raw performance is that this is with no attempt to sort or group the players by position. What does this curve look like for the top ten shortstops of all time? It would certainly be significantly lower, but again, that's an exercise for another day.

How do Griffey, Bonds, Thomas and McGwire stack up with these legends? Can we predict election to the Hall of Fame from graphs like these?

We'll find out soon enough in another Strikethree.com exclusive presentation.

For every home run Frank Thomas hits in 1998, Dave Paisley will donate $25 to the Society for the Rehabilitation of Usenet trolls. Make a pledge today at drdjp@strikethree.com.