Pitcher Advanced Metrics Studs and Duds - Chase Rate For Week 19

August 3, 2021

Connelly Doan examines pitchers whose particular chase rates could make them worth adding or dropping in fantasy baseball for Week 19.

Welcome back to RotoBaller’s Statcast pitcher Studs and Duds article series! Each week I have selected an advanced stat, chosen two top performers and two under-performers, and analyzed what those stats could mean for future fantasy output. This week I will focus on a metric that can have interesting implications for fantasy production: chase rate.

Chase rate is the percentage of swings hitters take at pitches outside of the zone. It is advantageous for pitchers to get hitters to chase because pitches out of the strike zone are more difficult to hit well and more difficult to hit in general. If a pitcher can find success without having to come into the strike zone then it indicates that they are deceiving hitters. A high chase rate can lead to more strikeouts and soft contact, which I have spent a good deal of time discussing throughout this series.

As I have done throughout this series, I will not focus on obvious fantasy studs for this article. There may still be a bit of time left before fantasy trade deadlines, so identifying players who could solidify your roster or hinder your chances of making the playoffs is key. With that in mind, let's take a closer look at some chase rate studs and duds!

Chase Rate Studs

All stats current as of Sunday, August 1, 2021.

Jordan Montgomery, New York Yankees

(4-5, 3.78 ERA, 1.19 WHIP, 31.6% Chase Rate)

This first pitcher is putting together his best season since his rookie debut in 2017. Jordan Montgomery has always been a fantasy hopeful, but hasn't really provided much value over the past several seasons. He has turned things around so far in 2021, compiling a 3.78 ERA, 1.19 WHIP, and 24.3% strikeout rate. One metric that stands out is his 31.6% chase rate, a mark that is 10th-highest among qualified pitchers. Has this played a part in Montgomery's success, and should fantasy managers expect it to continue?

Montgomery has an interesting pitch mix, throwing five pitches at least 10 percent of the time. His primary pitches are actually his curveball (23.9% usage) and changeup (23.6% usage). Not surprisingly, his curveball has the highest chase rate of his pitches at 42.9%. He has located the pitch well, keeping it in the bottom (and outside) of the zone. He doesn't have a ton of movement with his pitch, with 13% fewer vertical movement and 83% fewer horizontal movement. However, he is able to get a few different looks with the pitch in terms of his spin direction, leading to a solid 21.1% swinging-strike rate. This theme manifests itself across Montgomery's pitches out of the zone, as he has a 47% swing-and-miss rate on his pitches thrown out of the zone.

Montgomery has implemented an unusual approach to his pitch mix this season, but it has proved relatively successful. He relies heavily on off-speed pitches, which hasn't led to a ton of strikeouts but has led to a lot of chases, swings-and-misses on those chases, and an above-average batted-ball profile. He may not be the most exciting fantasy pitcher, but he has proven to be a high-floor option in both roto and points leagues this season. With an improved lineup to support him, I see no reason that Montgomery cannot continue to offer middle-of-the-rotation support for fantasy managers for the remainder of the season.

Ryan Yarbrough, Tampa Bay Rays

(6-4, 4.38 ERA, 1.19 WHIP, 31.2% Chase Rate)

This next pitcher has always been a useful streamer or back-of-the-rotation option for fantasy despite not being the most exciting option. Ryan Yarbrough is once again providing decent numbers this season, with a 4.38 ERA, 1.19 WHIP, and a 31.2% chase rate that is 13th-best among qualifying pitchers. How does chase rate contribute to Yarbrough's success?

Yarbrough's chase rate makes sense given his overall pitcher profile. He is not an overpowering pitcher, with his cutter averaging just 82.6 MPH. As such, he has to pitch with good location to be effective. His unorthodox mechanics contribute to his deception, but he ultimately has to hit his spots, which he has mostly done. He pounds the low-outside corner for right-handed hitters with his changeup and inside part of the plate for right-handed hitters with his slider/curveball. These two pitches have been his most-chased pitches, with a 43.1% chase rate with the changeup and a 34% chase rate with his slider/curve. He doesn't get many swing-and-misses on his pitches out of the zone or on any of his pitches in general, but his location has led to a solid batted-ball profile. Yarbrough's average exit velocity and hard-hit rate are both in the top-three percent of baseball. His 4.22 SIERA indicates that he has performed as expected to this point.

Yarbrough's fantasy upside is limited by his pitching style. He doesn't get many swings-and-misses and doesn't strike many hitters out. However, he has worked well with his skill set and has seen positive results in the form of a lot of chases on pitches out of the zone, leading to poorly-batted balls. Yarbrough has performed as advertised this season and has offered fantasy managers consistent performance as a back-end rotation piece. He may offer more value in points leagues than roto leagues, but he shouldn't hurt fantasy managers.

Chase Rate Duds

All stats current as of Sunday, August 1, 2021.

Tyler Mahle, Cincinnati Reds

(8-3, 3.71 ERA, 1.23 WHIP, 25.8% Chase Rate)

This pitcher is one who fantasy managers have had hopes for since he started his big-league career. Tyler Mahle finally put things together in 2020 and has continued in 2021, putting together an 8-3 record with a 3.71 ERA, 1.23 WHIP, and 28.2% strikeout rate. However,  his 25.8% chase rate is tied for seventh-lowest among qualified pitchers. How has Mahle found his success if not from getting hitters to chase pitches?

Mahle's numbers present an interesting picture. He does not get a lot of swings at pitches outside of the zone, but he does throw a lot of pitches out of the zone; his out-of-zone rate of 53% is tied for seventh-highest among qualified pitchers. The fact that he relies so heavily on his fastball (52.8% usage) could explain this. His fastball does have above-average vertical and horizontal movement, but hitters may be able to better-follow it into the plate and therefore lay off of his offerings out of the zone.

The good thing is that Mahle has done well in the zone. First, the contact he has allowed is above-average; his average exit velocity and hard-hit rate are in the 55th and 74th percentiles, respectively. His 3.83 SIERA supports this. Also, he has gotten a ton of swings-and-misses in the zone; his 23.4% swing-and-miss rate on pitches in the zone is tied for seventh-highest.

All in all, Mahle has produced solid numbers this season and has done some things well. He has an above-average batted-ball profile and has gotten swings-and-misses in the zone, leading to a high strikeout rate. However, he relies heavily on his fastball for a starter, throws the ball out of the zone frequently, and doesn't get many chases. Hitters don't have to get chases to be successful, but I worry that Mahle's pitching approach could come back to hurt him at some point.

Charlie Morton, Atlanta Braves

(10-4, 3.69 ERA, 1.15 WHIP, 26.7% Chase Rate)

Our final pitcher was a late bloomer in fantasy but has been a staple for seasons. Now 37 years old, Charlie Morton still has it, compiling a 10-4 record this season with a 3.69 ERA, 1.15 WHIP, and 27.7% strikeout rate. One number that hasn't been great is his 26.7% chase rate, which is 13th-lowest among qualified pitchers. Let's dive a bit deeper into how the veteran has gotten it done.

The fact that Morton doesn't throw a ton of pitches out of the zone (49.5%) helps to negate the fact that he doesn't get a ton of chases. Further, his 46.9% out-of-zone contact is 10th-lowest among qualified pitchers, which also helps. Along these lines, Morton's above-average exit velocity and hard-hit rate with his 7.7-degree launch angle have meant that he has limited damaging contact. He also has managed a 12.3% swinging-strike rate overall, so he has gotten plenty of swings-and-misses. All of this could be due to a nice pitch mix. Morton has thrown his four-seam fastball and curveball almost equally, keeping hitters off-balance.

Morton is a proven veteran pitcher, and has kept it up in his age-37 season. He has above-average numbers across the board, despite not getting hitters to chase that often. Everything points to Morton being a pitcher fantasy managers can trust down the stretch as they push for the fantasy playoffs.

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