DVS Analysis: MLB Current vs. MLB Past

 The start of the 2015 MLB season was strikingly similar to the start of the 2014 Season; over 100 players started the season on the disabled list.  In 2013, we learned over one-third of all active pitchers in MLB have had a Tommy John Surgery at some point in their career.  This year, 115 players started the season on the DL, and of those 115, over 60% are on the DL because of a throwing related injury. 

The injury epidemic within the game of baseball is real.  Everyone is searching for answers and judging from our data; the epidemic is here to stay.  We say this for two reasons. First, one of the best predictors of future injury is to look at our youth population and see how their throwing mechanics correlates with the current pattern of an average MLB pitcher.  Second, we can compare the average mechanical pattern of today's MLB pitchers to the average mechanical pattern of former MLB pitchers.

For the purpose of this article, we will compare the DVS Scores of all pitchers born before 1975 (MLB Past Era) to all pitchers born after 1975 (MLB Current Era).  The year 1975 has significant value to our data because this is when we could see quantifiable changes in the average DVS score for pitchers within our data set.  

Average DVS Score

 MLB Past Era (MLBP) = 13.6 / MLB Current Era(MLBC) = 12.8


We label all players born after 1975 as the MLB Current Era. The MLBC suggest since 1975, DVS Scores have steadily declined on average among MLB pitchers. This same pattern is present in our youth population as well. As of 2015, DVS scores continue to gradually decline amongst baseball pitchers of all ages, indicating we are still within the MLBC.  The tables below summarize the two era's distribution of DVS scores and correlates the scores to total innings pitched and total number of injuries.





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In order to compare DVS Score distribution between the two era's, let's refer to the two pie charts listed above which illustrate the breakdown. 

Overall, it's apparent that the MLBC has a much higher distribution of DVS Scores (38%) that lie within the "Less than 12" category relative to the MLBP (24%). This same pattern was evident in each ascending DVS scoring category, with the only exception being the "12 and 13" category. For the most part, as DVS scores increased, the current era's distributions were consistently lower relative to the past era's distributions. Simply put, the MLBC had a greater distribution of bad DVS Scores compared to the MLBP, which had a much higher distribution of good scores. This distribution could give valuable insight into the current injury epidemic and why injuries are up at an alarming rate. 

Analysis Highlights:

  • 70% of pitchers within the MLBC have a DVS Score of 13 or less compared to only 51% in the MLBP. This means that 19% MORE pitchers fall under the higher risk categories.
  • In terms of the lower risk categories, 27% of pitchers in MLBP had a DVS Score of 16 or higher compared to just 14% in MLBC
  • Only 30% of all pitchers in MLBC have a DVS Score higher than 14.


This relationship is one of the most alarming takeaways from this article. Essentially, we are looking at the average number of innings pitched prior to the onset of an injury, and then comparing this number between each DVS Score category. Let's refer to the tables 1 & 2 above to investigate this more in-depth.  

Analysis Highlights:

  • For both era's, As a pitcher's DVS Score increases, the number of innings until the event of a major injury increases.
  • Starting with the "Less than 12" category, it's evident that the current era averaged approximately 120 less innings prior to the onset of a significant injury. As DVS Score increased through each respective category ("12 and 13," "14 and 15," and "16 and Up"), this gap widened as the current era averaged approximately 272, 260, and 544 less innings compared to their past era counterparts.


It's important to note, that not all players in the MLB Current Era have stopped accumulating innings. Several players within our data set our currently active in and have not finished their career.  However, this does not affect how often the rate at which this particular data set gets injured. The data suggest that far more pitchers are getting hurt more frequently and accumulating less innings in the process.  

Analysis Highlights:

  • In the MLB Past Era, A dramatic increase in innings pitched occurs when a pitcher moves from a DVS Score of a 15 to a 16; 2464 to 3581.
  • In the MLB Past Era, a pitcher with DVS Score of 12 or below still managed to accumulate over 2,000 innings.
  • On average, pitchers in the MLB Past Era more than doubled the amount of innings pitched (2636) in their career compared to the MLB Current Era (1013).


Perhaps the greatest finding through our initial data collection and scoring was the gradual shift in the average mechanical pattern between the two eras. The visible shift in mechanics, which can now objectively can be seen through a decline in DVS Score distributions within MLBC,  alludes to a strong connection between the role of pitching mechanics and throwing related injuries.  

The image below highlights a typical delivery within our MLBP data compared to a typical delivery in our MLBC  data. 


A variety of factors exist within the game of baseball that have contributed to a steady decline in pitching mechanics over the last thirty years.  But why in a society with the latest medical training, equipment, and information are pitchers losing the battle against surgery and shortened careers?  

Players born before 1975 didn't have the advantage of readily accessibly information through computers, tablets, YouTube, etc.  However, the data suggest their pitching mechanics on average were superior.  In today's modern culture of pitching methodology, everyone seems to be an expert on how to throw a baseball.  At DVS, we want to remove the subjectivity of any one teaching style and prove objectively how at risk any pitcher may be through their DVS Score.  

- Justin Orenduff