Perhaps the greatest right-handed hitter in the history of Major League Baseball, Albert Pujols inspires fear into the hearts of opposing pitchers and managers alike. In the past 10 years, he has led baseball in intentional walks, and not by a small margin either — he has 72 more intentional walks than second place (Vladimir Guerrero). This is not an insignificant sum. Because the value of an intentional walk is about a 10th of a run, Pujols’ 251 career intentional walks are equivalent to about 2.5 wins. That means on average, Pujols gains about 2.3 runs per season purely out of managerial fear.
This postseason has fared no differently for the Cardinal’s legendary first baseman; he’s already gotten seven intentional walks. But this tells us nothing about how pitchers approach Pujols — intentional walks don’t contain information about instances where pitchers simply pitch around him. To gain a greater grasp of the Pujols fear dynamic, we should visually examine how pitchers approach him:
This graph shows the difference between two different distributions. The first being the pitches thrown to Pujols from 2008 to 2011. The second is a random sample of 15,000 pitches thrown to right-handed batters in 2011. Comparing the two sets of pitch locations allows us to see where the league is pitching to Pujols, with the context already accounted for. Blue locations indicate areas where Pujols was pitched to less than an average right-handed batter, and red indicates locations where Pujols was pitched to more than right-handed batters. The graph is from the catcher’s perspective, so the left side of the graph corresponds to the inside of the plate for right-handed batters and the right side of the graph corresponds to the outside portion of the plate to right-handed batters. The dotted box represents the strike zone.
As you can see, pitchers work very hard to avoid the middle of the plate — and pitches that are up. Instead, they throw more pitches to Pujols that are down and down-and-away. Neither of these results is surprising, but it’s always nice to have visual analysis confirm what we would intuitively expect. Of course, there are other methods to quantitatively assess pitchers’ approach to Pujols.
Zone % — more complicated than it seems
A simple way — at least ostensibly — to look at how the league pitches Pujols — compared to the rest of the league — is zone %. This is the percentage of pitches that are within the strike zone. But how do we define the zone? Are we talking about the rulebook strike zone, or the strike zone that umpires really call? Are these two zones even different? These questions introduce some subjectivity into zone %.
According to Mike Fast’s research, the rulebook strike zone and the called strike zone are not interchangeable. In the interest of accuracy, I’ll calculate zone % using these updated strike-zone definitions and PITCHf/x data. I find that the average zone % to right handed batters in the sample is 50.9 % and that the zone % to Pujols, across the past four years, is 46.7%.
But this does not consider the fact that Pujols is pitched to in a different distribution of counts than the league-average batter. This is significant because pitchers don’t throw the same proportion of pitches within the zone for every count:
There’s generally an inverse relationship between the polarity of the count (from the pitcher’s perspective) and the amount of pitches thrown in the zone. In other words, when pitchers are ahead they throw more balls, and when they are behind they throw more strikes. This means that the distribution of counts that Pujols bats in might have a significant effect on his zone %. In fact, if Pujols is in more batter-favorable counts than average, then his zone % is actually going to be inflated because pitchers throw more strikes when they are behind, versus in other situations.
To account for this, I made the distribution of counts the same for both Pujols and the sample. Once we do this, we find that the new, count-adjusted zone % for Pujols is 46.1% and that the adjusted average is 52.3%. This difference of 6.2% is larger than the initial estimate of 4.2%, albeit by a small amount. The zone % method does not give us the level of granularity of the visual method used earlier, but it does offer us one nice, overall number.
Despite pitchers’ greatest efforts to avoid giving Pujols anything to hit, he still finds ways to mash and get on base at a rate that few others can match. At this point, it’s very unlikely — if not inconceivable — that pitchers will ever develop a strategy to deal with him.
References and Resources
*PITCHf/x data from MLBAM via Darrel Zimmerman’s pbp2 database and scripts by Joseph Adler/Mike Fast/Darrel Zimmerman
*Research by Mike Fast on the actual called strike zone
*Tango’s linear weights