Dominican Ballplayers in MLB and the Provinces They Hail From

It shouldn’t come as any great surprise to a typical baseball fan that Dominican players play an outsized role in Major League Baseball today. In fact, the Dominican Republic, which has a population roughly just 3.3% that of the United States, supplies MLB with upwards of 10% of its players; Major League Baseball and baseball fans are better off because of this. After all, who wants to live in a baseball world without Nelson Cruz or Fernando Tatís Jr., for instance?

So, with this point in mind, the following takes a look at players from the Dominican Republic. More specifically, where in the DR players were born and when they made their way to MLB. What follows will be split into three brief sections: a description of the data utilized, some insights into the growth of the DR’s influence in MLB, and finally some map-based depictions of the players’ provinces of birth within the Dominican Republic.

I: The Data

Data for this piece comes from two places: the player data (players, WAR, years active, date of birth, location of birth) was pulled from Baseball Reference and the population/province data was pulled from Wikipedia (not exactly academic, I know).

Baseball Reference features the option to group players by nationality: at the time that this Dominican player dataset was pulled (7/29/2021), there were 813 players listed as being born in the DR who had then gone on to play in MLB. After exporting data from the Dominican Republic’s BR page, there was some light data wrangling to do.

First, the positional history of each player had to be made use of in order to classify each player as either primarily a pitcher or a hitter (no Shohei Ohtani classification dilemmas here). Next, birthplace data had to be broken up into two fields for provinces and cities, respectively. As a last step, each player was assigned a decade which they would be sorted into based on when they played. This was done by taking the average of each player’s debut season and final season and rounding that average to the nearest tens place (e.g. a player who played from 2008 to 2013 would be assigned the 2010 decade).

The city data was a little messy or incomplete in Baseball Reference, but province data appears to have all been there. Of the 32 provinces in the Dominican Republic, those 813 eventual MLB players had been born in all but 3.

II: Trends & Insights

Before addressing the “where”, let’s address some of the “when.” Because data for player positions and primary decade of play were taken, data were first grouped by those fields. This view immediately challenged one particular preconception I personally had regarding Dominican players: that there have been more Dominican-born hitters than pitchers, which is in fact incorrect.

The Dominican presence in MLB looks to have really taken off around the 1990s. And, indeed, until around that point most of the Dominican big leaguers were in fact position players, as opposed to pitchers. Pitchers, in sheer total of players at least, have eclipsed hitters in the 21st century.

The number of Dominican players continues to rise, too: both the 2010 and 2020 decades feature 241 players, but it is only 2021; there is plenty of time for this next generation of players to make their impact on the game.

Baseball Reference also kindly includes player WAR (bWAR) in its original dataset. Given this, I pulled the average bWAR per player type and decade, which is given in the table below.

This second chart begins to elucidate the seemingly hitter-heavy presence of Dominican players: on average they have been more productive, though fewer in number over the last few decades. In fact, the Top 10 list of players in bWAR, which you can access on the same BR page by sorting for bWAR, includes just two pitchers: Juan Marichal and Pedro Martínez.

However, perhaps the most eye-opening point from the chart above is the average bWAR for hitters whose careers were primarily around 2010: those players were worth nearly 10 bWAR on average. That group was boosted by all-time greats like Albert Pujols, David Ortiz, and Adrián Beltré, but the group as a whole is nonetheless incredibly impressive.

Next, a look at the highest bWAR player from each province in the Dominican Republic.

This is an interesting breakdown if only to illustrate the considerable variance across provinces in the Dominican Republic. Rafael Furcal, for instance, represents one of the most successful big league players, yet the Dajabon province has produced just 4 big leaguers. Another peculiar finding is the Santo Domingo province, which represents a huge percentage of the DR’s population (and also happens to surround the Distrito Nacional) has produced very little in the way of MLB players relative to the smaller Distrito National which it engulfs.

To better contextualize things, this final chart offers a WAR to Population ratio, or “WAR per MLB player capita” of sorts, with population data coming from Wikipedia.

III: Maps

This third section features three maps, created in Tableau, which feature the following: number of MLB players by province, cumulative bWAR by province, and average player bWAR by province. These charts are rather self-explanatory so I will spare you my commentary aside from brief captions.

The presence of Dominican players has been on the rise in recent decades and there is no evidence to suggest that trend is changing anytime soon. There are a plethora of implications to this phenomenon, both for the players themselves as well as MLB, none of which are covered here. As one potential avenue for more insight (provided by someone far and away better equipped to provide it) into these matters I would recommend Dominican Baseball by Alan Klein. Still, this brief post hopefully offers some insights and points of interest nonetheless.

The original data in the WAR Leaders by Province chart above had several errors that have been noted by helpful readers. I have since updated that chart to include Felipe Alou as the leader from San Cristobal, Carlos Peguero from Elias Pina, and José Paniagua in San Jose de Ocoa. Thank you to those who offered feedback!