Season Pitch Counts Provide Insights

Let’ look at the 200 pitchers with the highest number of pitches in the last decade (2012 through May 2022 per Baseball Reference).

Each ten pitchers (in a ranked list) were combined to calculate averages of pitches per homer, pitches per walk, pitches per strikeout, and a rough estimate of pitches per season within the last ten seasons.

The following graphs show that the pitchers with the highest thrown pitches were in general better in pitches per home run, pitches per walk, and pitches per strikeout.

With the long term trend of increasing homers, it’s not surprising that pitchers who go the longest (most pitches) between homers are valued. What is interesting is that they sustain that value while throwing the most pitches. There is a big gap better at the 85th percentile and a smaller gap at the 60th percentile of pitches thrown.

Data from Baseball Reference.

The differences in pitches thrown per walk are less dramatic and have more noise than pitches thrown per homer. I’m not sure of the reasons.

Data from Baseball Reference.

Pitchers who quickly get strikeouts (least pitches per strikeout) are often pitchers who have the most career pitches thrown. There is a clear gap at the 75th percentile of pitches thrown in the last ten seasons. Perhaps experience matters.

Data from Baseball Reference.

Top 50 Pitchers in Thrown Pitches

The top 50 pitchers (in total pitches thrown in the last decade) threw more pitches per year within their span than the next 150 pitchers (2559.9 vs 1862.7 pitches). The span of each pitcher is the first season pitched to the last season pitched within the decade.

Instead of looking at the most pitches thrown, let’s look those rare pitchers who started the decade pitching and continued to pitch this season.

Iron Men Pitchers

Iron men are the 43 pitchers (out of 200) who played in 2012 and continued playing in 2022. They are iron men because they pitched in the Majors over the span of a decade. Let’s compare their averages to the other pitchers.

The 43 Iron men pitchers’ had 16.8 pitches per strikeout, which was better than the 95th percentile of the pitchers who threw the most pitches. My conclusion is playing the most seasons in the Majors is more valuable experience than throwing the most pitches in the Majors.

The 43 iron men were better than the 157 non-iron men in the following:

• Pitches per home run (140.8 vs 129.5).
• Pitches per walk (54.4 vs 53.2).
• Pitches per strikeout (16.8 vs 18.4).

Iron man pitchers’ average of pitches per season in the last decade was LOWER than non-iron men (1858.3 vs 2087.7 pitches). In general, there may be a longevity advantage to throwing less pitches per season.

A worthy subject for investigation is how to specify a pitch threshold that when not exceeded increases years of pitching. Although that threshold could be unique to each pitcher, if I had to decide a general threshold, it would be 2280 pitches for two reasons:

• Only 12 iron man pitchers exceeded that average for the decade, albeit a few elite pitchers such as Zack Greinke and Madison Bumgarner would be exceptions to the threshold.
• The threshold would be exceeded by less than half of the non-iron men pitchers.

Seasons With Above Average Pitches.

The rough average of pitches per season of the iron-man pitchers was 1858. Let’s define seasons with at least 1858 pitches as above average.

Looking at the Diamondbacks from 2012 to May of 2022, every time the count of their pitchers with at least 1858 pitches increased compared to the previous season, the Diamondbacks had a better win-loss record. Every time the count of their pitchers with at least 1858 pitches decreased they had a worse win-loss record. The two exceptions were 2019 (more wins with reduced 1858 pitchers) and 2020 (less wins extrapolated to a full season with increased 1858 pitchers).

Madison Bumgarner is an iron man pitcher who leads the team with 11 seasons with at least 1858 pitches in his career (adjusting the 2020 requirement to 688 pitches, and counting 2022). Ian Kennedy is an iron man pitcher. He had 9 seasons with at least 1858 pitches in his career, although as a reliever he is unlikely to add to his total.

Current Diamondback pitchers on track to pitch 1858 pitches for the season are: Madison Bumgarner, Merrill Kelly, Zach Davies, Zac Gallen, and Humberto Castellanos.

Diamondback Pitchers This Season

Let’s look at the pitches by Diamondbacks starters and relievers. The following pie chart shows pitches thorn by five starters are about the same. Tyler Gilbert, the sixth starter, threw significantly less pitches. Not shown is Caleb Smith’s start, which was an opener by a reliever.

Pitches thrown through 1 June of the 2022 season. Data from Baseball Reference.

The following pie chart shows four tiers of relievers:

• Very High Pitches Thrown: Caleb Smith, Noe Ramirez, and Ian Kennedy.
• High Pitches Thrown: J.B. Wendelken, Joe Mantiply, Mark Melancon, and Corbin Martin.
• Medium Pitches Thrown: Kyle Nelson, Sean Poppen, and Luis Frias.
• Low Pitches Thrown: Edwin Uceta, Oliver Perez, Keynan Middleton, Taylor Widener, Tyler Holton, Matt Peacock, Paul Fry, Luke Weaver, Carson Kelly, and Jake Hager. Note that Paul Fry started pitching for the Diamondbacks on 1 June, with 27 pitches.

Pitches thrown for Diamondbacks through 1 June of the 2022 season. Data from Baseball Reference.