Comparing Pitchers in the 2023 MLB Season
Part of the struggle in building a roster in Major League Baseball is determining if a outlier performance from a player will be an anomaly in their career, or if they will continue that level of performance in the future. To try and answer that question, MLB analysts will look at player comparisons for said breakout player, and see if they line up well with established veterans who have been performing at a high level for an extended period of time. They also will look at comparisons for the established star player, and see if there are any young players with comparable underlying metrics who may not be performing at the top of their level. Using summarized data from Fangraphs on every pitcher who pitched in MLB in 2023, I will look at one starting pitcher who has had sustained success — Logan Webb — , a breakout starting pitcher from 2023 — Kyle Bradish — , and a relief pitcher with elite pitches but has had a bit of a rocky career — Matt Brash — and find their closest comparison based on a set of statistics I arbitrarily grouped together to measure similarities between pitchers.
All in all, there were 299 different statistics in the original dataset. With it being official data from a reliable source, there was no cleaning that needed to be performed. I narrowed that down to nine stats that I felt demonstrated a pitchers’ full ability to be successful or not, as well as being an accurate demonstration of finding similar pitchers. These metrics often factor out variables that the pitcher cannot control, such as strength of defense, and focuses moreso on a pitchers actual skill. After filtering down to pitchers who have thrown a minimum of 25 innings to eliminate position players and pitchers who do not have a sufficient sample, we narrowed the sample down to 519 pitchers. The data was then normalized to prevent skewed data, and a Euclidean Distance methodology was applied to get the results.
Logan Webb:
Webb has solidified himself as a top 10 starting pitcher in the game over the past 3 years, culminating in a 2nd place finish in the Cy Young voting last year. He is currently entering his peak age of performance, and is someone projected to have continued success. When looking at the top 10 pitchers most similar to him, we have one pitcher with sustained success as a starting pitcher (Kevin Gausman), three starting pitchers who did not have as good surface level stats as Webb (Jesus Luzardo, Mitch Keller, and Aaron Civale), and four relief pitchers who have been successful in their respective roles in recent history (Joe Jimenez, Seth Lugo, Matt Moore, and John Brebbia). The final two pitchers (Gabe Speier and Adbert Alzolay) are younger, less established pitchers. From Webb’s standpoint, having similar comparison scores to pitchers who have been able to maintain their success bodes well for his future. Assuming there are no injury issues, he should be able to continue performing at a high level for the foreseeable future.
When looking at Luzardo, Keller, and Civale, they have all had some levels of success in their careers. They struggled early, but seem to have corrected those issues and had strong performances last season. Being grouped with these other pitchers provides hope that they can continue progressing into becoming the best versions of themselves.
There is also hope for Speier and Alzolay. Although they will most likely not be converted to starting pitchers, having strong connections to other successful relief pitchers makes me believe they can continue their upward trend from last year.
Kyle Bradish:
Bradish is the epitome of carrying over the hot hand into a new season. He ended 2022 on a very strong note after being one of the worst pitchers in the first half of the season, and continued his success for the entirety of 2023, finishing 4th in AL Cy Young voting. But his abrupt breakout still raised questions: Would Bradish keep up his strong performance from the previous 1.5 years, or would he regress to the pitcher he was prior? Unfortunately, he has been injured to start 2024, but when looking at comparable pitchers, he is in some good company. His most recent comp is Corbin Burnes, arguably a top 5 starting pitcher in baseball. He won the NL Cy Young Award in 2021, and has been selected to the All Star Game the past 3 seasons. If Bradish can even somewhat represent what Burnes has been, that would come as a huge success both for Bradish and his team.
Other pitchers that rank in the top 10 of similarity to Bradish include 4 of the best closers in baseball from 2023 — Jordan Romano, Paul Seward, Clay Holmes, and Jhoan Duran. While these pitchers are all relievers, it does show that Bradish could have a future in the bullpen if he does not continue his high performance as a starter. His talent and ability to pitch is there, it is just a question of if he can keep it up as a starter, or if he will end up in the bullpen.
Devin Williams:
Since his first full season in 2020, Williams has arguably been the best relief pitcher in all of baseball. He has built up a track record of success, has proven to be successful in different roles, and has just been a model of consistency for relief pitchers. With starting pitchers throwing fewer and fewer innings with each passing year, relief pitchers are becoming more valuable. A team being able to acquire and/or develop a pitcher of Williams’ quality could push them over the edge from being a middling team to a contender.
Using Williams as a baseline for evaluating other pitchers can be useful in finding your next shutdown reliever. From this list, the list of successful relief pitchers is headlined by Josh Hader, while Jose Alvarado, Joe Kelly, and Emilio Pagan have had successful careers as relievers as well. Kevin Ginkel and Robert Suarez stand out as players with the potential to take their game to the next level. After having strong seasons in 2023, being similar to Williams provides optimism that they can continue pitching well into 2024, and hopefully beyond. However, the name that stands out the most to be is Brandon Woodruff. While he is a successful starting pitcher, he has been hampered by injuries the past couple seasons. With him having strong numbers that compare well to the games best relief pitchers, he could be a prime candidate to move to the bullpen once he becomes healthy again. The data suggests he could be successful, and having him throw less innings could provide useful in keeping him healthy.
Conclusion:
Using players as a baseline to find comparable pitchers to discover breakout stars, continued success, or a pitcher about regress is very important in roster construction, and is something that will continue to be used. However, we do need to remember there are multiple ways to go about it. For example, I did not compare pitchers in similar roles; for example, some of the comparisons might not have much validity to them, because similar pitchers may never be compared due to them having different roles. Additionally, the stats I selected to measure may be different than what someone else uses, leading us to have different results. I may have different thoughts on what stats matter the most, which could lead to a certain type of pitcher being favored more.
Attached is a link to my GitHub repository that contains my code for this project:
https://github.com/jaronrichman/INST414-Module-Assignments/blob/main/Module%203%20Assignment.ipynb
