The history of 20-year olds in the majors


Mike Stanton had a monster set of games recently, knocking five home runs and driving in 11 runs in just two games. This recent outburst, combined with his impressive Spring Training sample from before the season, have renewed the calls for “Stanton in the majors.” Those who are making these calls cite the example of Jason Heyward, an equally young and impressive player who started on Opening Day for the Atlanta Braves and is hitting .224/.358/.448, good for a .360 wOBA and some over-the-top fanfare.

Let’s get this out of the way immediately: the Marlins will not promote Stanton until the end of this year unless there are some extremely dire injuries. The team does not need to get Stanton up here with Chris Coghlan, Cody Ross, and Cameron Maybin already in the big leagues.

But, let’s consider a promotion for Stanton from the developmental side. What does the past say young players out of high school who are promoted as quickly as Heyward was and as Stanton may yet be?

I took a look at all high school position players drafted in the first round from 1990 to 2004. In an attempt to homogenize the talent level of the selected players (I’ll explain why later on), I weeded out any draftees who were not ranked in the top 50 of Baseball America’s prospect rankings at some point during their minor league career. This gave me a sample of 57 players. I then split these players into two groups:

Group A: Players who received a call-up and at least 400 PA before their fifth year since their draft. For example, a player drafted in 1990 would have to have at least 400 PA by the end of the 1994 season to qualify for this group. Stanton would qualify if he could get 400 PA by next year, 2011.

Group B: Players who received at least 400 PA in their career.

There were 20 players in Group A and 27 players in Group B. Group A totaled 91959 PA over their careers, while Group B totaled 89531. I then took the career WAR up to 2009 for each player in either group and figured out a rate stat of WAR/700 PA to compare the two groups.


I’ll recap the highlights here, but you can check out the results yourself on this spreadsheet.

Among the 20 players who received the early callups, the group totaled 455.1 WAR and averaged right around 3.0 WAR per 600 PA, the equivalent of a player about one win better than average. The non-target group whom were not called up as early totaled 324.5 WAR, an average of 2.2 WAR per 600 PA, essentially average players. Both groups contain a wide variety of talents among their players. In the target group, you have names like Manny Ramirez, Alex Rodriguez, and Joe Mauer alongside such luminaries as Benji Gil, Jeff Francoeur, and Michael Barrett. Similarly, the other group has Chipper Jones as its top performer and Chad Hermansen at the bottom.

OK, so apparently early callups are about one win better per 600 PA better than the average top-ranked first round pick. So what does that tell us about Stanton and his chances?

Would you believe “nothing?”

This was a quick and dirty study, and there were a few problems with it. The primary problem I knew we would run into is that the talent spread of these two groups aren’t the same. Those players who are called up and stick are more likely to be better players anyway than those who do not receive and early call. I tried to minimize this effect by using only first-rounders and only players who were ranked in BA’s top 50 prospects, but those data are all opinionated and could easily be incorrect with regards to a player’s true talent. This difference in WAR/600 could easily be a difference in true talent rather than a difference in play due to their early callup.

So why do this study? A lot of times you hear people claim that a move like promoting Stanton should be done because “(Insert Player A) was so successful when (Team A) did it!” This historical reasoning makes little to no sense with regards to prospects. Prospects and analysis of prospects is still heavily dependent on scouting, and different players would naturally react differently to promotions to different levels. As knowledgeable as I think John or I are about prospects based on their stats, scouting and organizational information to which we are not privy is still very important to get the right readings on players. Applying a blanket statement like a certain group of players called up earlier is better than another ignores the individual nature of a given player.

So what can we do? Well, this study was flawed and probably gave us little quantitatively, but it is interesting to note that there is still a good spread in the early callup group. The fact that Stanton is being considered for this means the organization knows he is very talented. It’s up to their scouting department to ultimately decide how talented he is and how well he develops. Sure, he hit five homers in two days, but how will he do across a season’s worth of Double-/Triple-A pitching? I know he’s struck out 21.4% of the time so far this year, but how is he handling himself at the plate, and how are pitchers handling him? With the uncertainties of the minors, putting blanket curves or expectations of players is a lot riskier than doing so for the majors. I would say that we should continue to watch Stanton and his stats and allow the Marlins’ brain trust to come up with its own scouting evaluations. If we could put all that information together, maybe then we could find out the best way to handle Stanton’s progress. Until then, both sides are ultimately either wishcasting or taking shots in the dark.