Rookies, Classes and Classification: 2010

There’s a general tendency to classify our surroundings. In order to save space in our brains, we label routines, constructs and actions, and store them away. On the positive side, this allows us to master complicated concepts with relative ease. Imagine if you went into your morning commute with a fresh approach every day. You’d be late often. The negatives — perhaps outlined best by Aldous Huxley in The Doors of Perception — are that we fail to fully enjoy how fascinating daily moments can be.

Our appreciation of sports is no different. Even as we revel in the superlative singular performances, we often hasten to label them. Last year was either The Year Of The Pitcher or The Year of the Rookie depending on your focus. Plenty of energy has gone into parsing the former, but let’s instead look at the latter and maybe open a shut door. Was last year exceptional when it came to rookie performance? Were there more debuts, more average rookies or more exceptional rookie seasons last year than there have been in the past?

First, the debuts — if only because they are the easiest to find. Here are the numbers of players who debuted, by year, in the history of baseball.

On this level, 2010 was an interesting year. There were more debuts than ever — 186 players — the first time more than 180 players shared a debut year. Unlike the years between 1910 and 1912 and 1944 and 1947, the spike in debuts last year was completely unrelated to any war-time population or cultural changes. Last year also wasn’t an expansion year, either, something that might explain the large number of debuts in 1961, 1962 and 1969. Baseball debuts in 2010 were even ahead of the pace started during the renewed expansion era in the 1990s. In 1962, 127 players made their debut, or 8.1 per team. In 2010, 6.2 players made their debut per team but there was no recent expansion as a caveat. More players are debuting, even if it’s not more per team.

A debut tells us something about needs — usually a debut is precipitated by an injury or poor performance by the veteran who used to own that role — but we also want to know if 2010 was exceptional. Were there more good, young rookies, or did we see an influx of young role players fulfilling their duties before returning to the minor leagues? Here’s a graph that shows the number of rookie-eligible players who managed a 2.0 WAR or better by year. (Now we’ve moved away from debuts and are considering only the last years in which a player retained his rookie eligibility.)

Here, 2010 fails to live up to its classification as the Year of the Rookie. There were a good number of rookies given regular enough roles to accrue 2.0 WAR, but now 2010 doesn’t stand out from the pack. In fact, it fits right into a general trend. We’ve been using rookies more often and asking more of them in recent years.

Most likely, this is an artifact or even direct consequence of the arbitration process. Look back at the debuts graph, and you could almost draw a straight line from 1973, and the beginning of arbitration, upward through the last thirty years of baseball. Though the arbitration process does make young players more expensive than they had been under the Reserve Clause days, it also keeps their salaries under control compared to free agency. This general upward trend in the use of rookies seems to suggest that teams have realized that getting the most out of their cost-controlled players is sound baseball economics.

One more question remains. In a year where we treated to such excellent rookies as Buster Posey, Mike Stanton, Jason Heyward, Ike Davis, Gaby Sanchez, Starlin Castro and Austin Jackson, were we also treated to a singular, defining moment? Only 258 players in the history of baseball have had a rookie season with more than 3.5 WAR, so even after a cursory perusal of last year’s names, it seems like there were more than your usual share of excellent rookies.

Unfortunately, our effort to bring order to our world has perhaps failed us in this regard. Last year saw a good share of exceptional rookies, but it wasn’t such a standout year that it deserves the moniker of “Year of the Rookie.”

But, as with the many entities that we have (perhaps unfairly) classified in our daily lives, there were new ideas to be uncovered by engaging this previously labeled phenomenon with a fresh approach. We’ve discovered, perhaps, that 2010 was the Year of the Debut — if we’re forced to reduce these idle thoughts to classification through catchphrase. At least that title will help us remember 2010 once we are knee-deep in this year’s crop of exciting, young players.

H/T to David Appelman for his help and the rookie functionality on our leaderboards specifically, and for creating such a great site generally.