Pitcher Valuations: Single Season Projections & pERA Values

After focusing the 2021 prep on hitters for the last couple of weeks, it’s time for pitchers to take center stage. There is no way to hide that the following is mostly a data dump with a small bit of analysis. Welcome to mid-October 2021 draft prep.

Single Season Projections

These projections are about as simple as it gets. It takes a pitcher’s 2020 results and projections the pitcher going forward based just on those stats. With some pitchers completely changing their pitch arsenal, I find these projections are a better evaluation tool than multi-year averages. For a reference, here is the full write up on how they are created.

This year’s projections will have an even smaller value range because of the short season. There was just less time for pitchers to differentiate themselves from each other.

Also, there is some funkiness when a pitcher both starts and relieves. I didn’t make a judgment call on each one being a starter or reliever. Instead, I projected them for their most common 2020 role. Here are the top-30 pitchers based on projected ERA (full list).

2020’s Top-30 Starter Single Season Projections
Name G GS IP K/9 BB/9 HR/9 ERA WHIP
Devin Williams 60 0 61 14.3 3.1 0.7 3.17 1.04
Shane Bieber 30 30 180 13.8 2.9 1.0 3.33 1.08
James Karinchak 60 0 58 14.3 3.7 1.4 3.65 1.23
Jacob deGrom 30 30 175 13.0 3.0 1.2 3.65 1.18
Edwin Diaz 60 0 59 13.5 3.7 1.1 3.66 1.22
Tyler Glasnow 30 30 174 13.2 3.4 1.2 3.71 1.21
Corbin Burnes 30 30 174 12.8 3.5 1.1 3.75 1.22
Trevor Bauer 30 30 175 12.4 2.7 1.4 3.77 1.18
Aaron Nola 30 30 174 11.9 3.0 1.1 3.84 1.21
Dinelson Lamet 30 30 174 12.3 3.1 1.3 3.85 1.22
Caleb Ferguson 60 0 59 11.3 2.8 1.0 3.87 1.20
Kenta Maeda 30 30 175 11.1 2.5 1.2 3.89 1.18
Trevor Rosenthal 60 0 58 12.4 3.3 1.3 3.91 1.26
Lucas Giolito 30 30 172 12.2 3.5 1.2 3.92 1.25
Freddy Peralta 60 0 58 12.4 3.3 1.4 3.93 1.27
Brandon Woodruff 30 30 174 11.3 2.8 1.2 3.93 1.22
Tanner Rainey 60 0 58 12.4 3.3 1.5 3.94 1.26
Liam Hendriks 60 0 58 12.0 2.8 1.5 3.94 1.24
Jake McGee 60 0 58 11.9 2.9 1.3 3.94 1.26
Gerrit Cole 30 30 173 11.6 2.8 1.4 3.95 1.23
Victor Gonzalez 60 0 59 10.1 2.6 0.8 3.99 1.20
Triston McKenzie 30 30 173 11.5 3.0 1.3 3.99 1.24
Luis Castillo 30 30 172 11.3 3.3 1.0 3.99 1.27
Drew Smyly 30 30 171 11.9 3.3 1.3 4.00 1.29
Tommy Kahnle 60 0 59 9.3 3.2 0.1 4.01 1.20
Kevin Gausman 30 30 172 11.5 2.9 1.3 4.01 1.27
Jordan Romano 60 0 58 11.0 3.3 1.0 4.02 1.26
Yu Darvish 30 30 172 11.1 2.6 1.4 4.03 1.25
Tyler Duffey 60 0 58 11.0 3.1 1.1 4.03 1.25
Joe Musgrove 30 30 171 11.6 3.4 1.2 4.04 1.29

Notes

  • No surprises at the top with Devin Williams as the best reliever and Shane Bieber as the best starter.
  • Speaking of Williams, many non-closers (Karinchak, Ferguson, Peralta, Rainey, McGee, Gonzalez, Kahnle, and Duffey) populate the rankings. I wonder how many would have eventually become a closer if the season was the normal length.
  • While Triston McKenzie looks good here, I have my doubts going forward since he can’t maintain his velocity.
  • I expect to see Smyly and Gausman slowly climb draft boards after fantasy managers have a chance to dive in their results.
  • Oh Joe Musgrove, will I ever be able to quit you?

pERA

These rankings are the end-of-season pERA values. pERA is my ERA estimator based on each individual pitch’s results with the pitcher’s walk rate added in (full write up). One issue I found with pERA last season that the ever-changing baseball messes with the estimates. The main factor is that as the ball becomes more “juiced” more cans-of-corns go over the fence.

I used the 2016-2018 formula for the table since the ball flew similar to those seasons, but included all three with the full spreadsheet.

2020’s Top-30 Starter pERA Values (min 5 GS)
pitcher With control G GS
Jacob deGrom 1.43 12 12
Kenta Maeda 1.92 11 11
Shane Bieber 2.46 12 12
Zach Plesac 2.52 8 8
John Means 2.64 10 10
Clayton Kershaw 2.76 10 10
Tony Gonsolin 2.77 9 8
Yu Darvish 2.80 12 12
Luis Castillo 2.83 12 12
Masahiro Tanaka 2.85 10 10
Nathan Eovaldi 2.86 9 9
Gerrit Cole 2.88 12 12
Brandon Woodruff 2.99 13 13
Elieser Hernandez 2.99 6 6
Lucas Giolito 3.01 12 12
Kevin Gausman 3.01 12 10
Kyle Hendricks 3.02 12 12
Blake Snell 3.06 11 11
Sixto Sanchez 3.15 7 7
Josh Fleming 3.17 7 5
Ryan Yarbrough 3.26 11 9
Michael Pineda 3.26 5 5
Dylan Bundy 3.27 11 11
Tommy Milone 3.28 9 9
Framber Valdez 3.29 11 10
Jordan Montgomery 3.30 10 10
Trevor Bauer 3.32 11 11
Zack Wheeler 3.32 11 11
Aaron Nola 3.37 12 12
Joe Musgrove 3.38 8 8

Notes

  • The top names are as expected but John Means slides in at #5. His pitch results were great with all having a swinging-strike rate of over 10%. All of his struggles came down to a 2.5 HR/9 that led to a 7.06 ERA at home but only a 2.05 road ERA. Means looks to be a streaming option going forward.
  • Tanaka and Eovaldi seem out of place, but their 2020 seasons were decent besides the home runs (1.5 HR/9 or higher for both). It’s tough being a flyball pitcher in the AL East.
  • Tommy Milone needs to find a flyball pitcher-friendly park. His 18.8% K%-BB% was identical to Charlie Morton, Chris Paddack, and Lance Lynn.
  • Josh Fleming simply makes the rankings with the 64% GB% and low walk rate (2.0 BB/9). Now he must crack Tampa’s rotation.
  • Oh … more Joe Musgrove.





Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won four FSWA Awards including on for his Mining the News series. He's won Tout Wars three times, LABR twice, and got his first NFBC Main Event win in 2021. Follow him on Twitter @jeffwzimmerman.

5 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
Joe Wilkeymember
3 years ago

Not to say that Means is a viable fantasy starter, but he did allow three HR on balls that were less than 98 MPH off the bat, out of 32 LD+FB that were lower than 98. League-wide rate was 251 out of 13763, or 1.82%. I know he plays several games at Yankee Stadium, but even then, only 2.77% of <=98 EV were HR there. Means is at 9.38%. When you're talking about <50 IP, one or two HR makes a huge difference.

I mean, look at this garbage: https://baseballsavant.mlb.com/sporty-videos?playId=d49c2fe3-037c-499c-8836-b1e0abdef3a0

weekendatbidens
3 years ago
Reply to  Joe Wilkey

Small sample sizes will skew the typical statistics we rely upon to evaluate pitchers (and hitters). This pERA value does seem to expose some of it quite nicely. And your evidence shows nicely how Means was facing some inflation of his home run rate. So thank you for pointing this out.