Pittsburgh Pirates: Most Valuable Pitches During 2020 Season

The Pittsburgh Pirates are going to bring back two pitchers who threw the team’s most valuable pitches through the 2020 season. Who were they and how did they fare?

This offseason the Pittsburgh Pirates have traded away their two best pitchers in Joe Musgrove and Jameson Taillon. While this is part of the rebuilding process, the Pirates still have some interesting names going into 2021. Today, I want to look at some singular pitches. What pitches were the most valuable to the Pittsburgh Pirates in 2020?

I will be measuring this by Baseball Savant’s measurement, run value. Run value is defined by Baseball Savant as “the run impact of an event based on the runners on base, outs and, ball and strike count.” This is measured through a per-pitch basis compared to a per-plate appearance basis. The lower run value you have, the more valuable the pitch is. This is further expanded upon by Tangotiger.

Among the Pittsburgh Pirates’ starting pitchers, Chad Kuhl’s slider had the best run value mark of any pitcher. This pitch sat with a -6 run value according to Baseball Savant. Kuhl saw a major change in repertoire as he used his slider 34.5% of the time compared to just 19.8% in 2018 and 2017.

Kuhl’s slider averaged out at 87.8 MPH. Batters had a hard time barreling up the pitch with a hard hit rate of just 30.2%. They also only managed a .194 batting average, .244 wOBA and  .254 slugging percentage against the pitch. In terms of the expected stats, Kuhl had an xBA of .237 and xSLG of .359 with his slider. Although he did outperform his expectations, his expected stats are still very good.

Kuhl got batters to whiff at the pitch 39.7% of the time, which ranked 69th out of 190 total qualified pitchers who threw sliders in 2020. To go with that, he had a strong 25.3% and 32.4% strikeout rate. These also were very good marks for sliders in baseball during 2020.

While Kuhl’s slider had the highest run value, the best pitch in terms of run value per 100 pitches is another one of his breaking balls. Kuhl’s curveball recorded a -2.8 run value/100 pitches during 2020, which was the highest mark among all Pirates’ pitchers.

Like his slider, this was another pitch Kuhl saw an increased usage of in 2020. After having used it just 6.3% of the time in 2017 and 13.1% of the time in 2018, Kuhl started to throw his curve 17.6% of the time in 2020. Overall, the pitch was very effective. With opponents having a .071 batting average, .179 slugging percentage and .124 wOBA against this breaking ball, it was one of the most effective in the sport during 2020. Both the opponent BA and wOBA ranked in the top 3 and the opponent slugging mark ranked 19th among the 91 pitchers who threw enough curveballs to qualify.

Opponents barely made hard contact with a 15.1% rate, the 5th best mark among qualified pitchers. This led to extremely strong expected stats including a .114 xBA (9th best in baseball), .226 xSLG (22nd best in baseball) and .157 xwOBA (10th best in baseball. He got a ton of strikeouts with the pitch with a 51.7% strikeout rate, which was the 14th highest K% for a curveball in baseball. He also had a solid 38.5% whiff rate and 25.9% put out percentage with his curve. Kuhl’s curveball has always had the potential to be a devastatingly good pitch, so it’s good to see that he’s starting to use it more.

While Kuhl has the two best pitches for the Pirates’ starters, Geoff Hartlieb owns the best run value and run value/100 pitches for their relievers with his sinker. Hartlieb’s sinker had a -5 run value mark and -2.2 run value/100 pitches mark throughout the 2020 season.

Hartlieb’s sinker averaged out at 93.6 MPH. It became his primary pitch in 2020 as he used it 51.1% of the time. In comparison to 2019, he used his sinker just 29.5% of the time. Hartlieb had very good bottom line numbers with his sinker. Opponents only managed a .195 batting average and .220 slugging percentage against it. However, he gave up a fair amount of hard hit balls with a 37.8% hard hit rate, which led to an unimpressive .259 xBA, .314 xSLG and .380 xwOBA.

Still, the pitch is seen as something that could be an extremely strong weapon. Not only is he able to reach upwards of 96 MPH with the pitch, but it has tremendous break. He averaged 24.9 inches of drop, which was 4.1 inches above the average and 15.8 inches of break which was 1.3 inches above the average sinker. It also pairs well with his wipeout slider.

Both Kuhl and Hartlieb have the potential to be really important pitchers for the Pittsburgh Pirates moving forward. While they were effective with these two pitches, their overall pitch repitoier could make them breakout candidates going into 2021.