Changing Fastballs (4/18/19)

After going over the pitchers who changed their velocity from 2018 to 2019, the pitchers who have seen changes this year get highlighted today. For the first week or so, pitchers who saw major adjustments were in the crosshairs of the fantasy community. But who from that list kept the changes? A pitcher’s talent shouldn’t get anchored to one early-season report. It’s time to dive in.

About the data

  • I use the fastball’s average spin rate and velocity along with the pitcher’s overall Zone% to come up in the Injury metric. With spin rate, I’ve seen pitchers try to keep up their velocity while dealing with an injury and the pitch’s spin changes. As for Zone%, if a pitcher is having issues finding the plate, they may have something mechanically wrong.
  • The Injury value ranges from a -100 (several negative forces are at work) to +100 (major improvements).
  • A pitcher can have more than one fastball in the table
  • When examining the 2019 data, I’m comparing velocities from the past week to fastballs thrown before this past week.
  • All the numbers are available in this overall spreadsheet.

First, here are the pitchers who have seen their fastball improve after some early season struggles and my thoughts on a few of them.

Improving Fastballs
Name Pitch Velo Spin Count Zone% Velo Spin Count Injury
Chris Sale FF 92.4 2271 109 50% 95.5 2347 33 114
Aroldis Chapman FF 96.8 2479 58 55% 99.9 2608 6 113
Hunter Wood FF 92.1 2445 42 54% 93.1 2565 11 76
Eduardo Rodriguez FF 92.6 2179 120 45% 93.6 2270 48 64
James Paxton FF 95.6 2320 258 55% 97.0 2382 80 63
Harrison Musgrave SI 90.6 2410 24 50% 91.9 2462 7 58
Martin Perez FF 92.9 2202 94 49% 95.2 2171 16 56
Harrison Musgrave FF 91.5 2519 31 50% 92.9 2524 7 55
Kelvin Herrera FF 94.4 2168 41 49% 95.8 2220 9 50
Tim Collins FF 92.2 2241 32 45% 92.5 2277 24 49
Mike Fiers FT 89.2 2274 54 50% 90.0 2357 20 48
Jake Petricka FT 93.2 2083 27 45% 94.0 2105 14 47
Yu Darvish FF 92.9 2486 138 46% 94.0 2577 33 44
Jason Vargas FT 84.7 2210 74 43% 86.2 2224 22 43
Kirby Yates FF 93.2 2314 104 43% 93.9 2409 23 43
Chris Martin FF 95.5 2316 42 63% 95.7 2371 10 40
Wade LeBlanc FF 85.9 1966 12 46% 86.4 1998 7 39
Chris Devenski FF 93.2 2342 48 54% 93.3 2394 22 38
Reynaldo Lopez FF 93.8 2075 241 50% 94.9 2103 63 38
Wei-Yin Chen FF 90.8 2094 105 53% 91.6 2104 27 37
Aaron Sanchez FF 94.1 2352 112 50% 94.4 2399 62 37
Carlos Rodon FF 91.9 2173 211 43% 92.9 2236 52 37
A.J. Minter FF 95.1 2309 41 53% 95.5 2352 17 37
Dereck Rodriguez FF 90.6 2081 126 47% 91.8 2108 36 37
Jack Flaherty FT 92.5 2069 35 45% 93.3 2116 8 35
Buck Farmer FF 94.8 2359 25 52% 95.5 2333 12 33
Phil Maton FF 90.1 2616 35 47% 90.8 2644 8 31
Ty Buttrey FF 95.9 2204 61 51% 97.0 2228 6 30
Chris Archer FT 93.1 2155 43 46% 93.6 2217 12 30
Brett Anderson SI 90.2 1852 169 46% 90.7 1900 50 30

● Chris Sale: Everyone and their mother has a hot take on Sale. All, I have to say is that his velocity and spin were back to 2018 levels in his last start. His fantasy value is slowly creeping up.

His perceived value is down with most recent one-for-one trades at Yahoo (list updates as new trades come in) he was traded from Zack Greinke (x2), Masahiro Tanaka, and Clayton Kershaw. I would trade any of those three for Sale, especially now that Sale looks to be improving. Here is how my Twitter followers responded when I posed the question to them.

● Aroldis Chapman: His fastball started the season averaging under 97 mph and his last six pitches averaged 99.9 mph. No worries for now.

● Eduardo Rodriguez: Rodriguez was another Red Sox pitcher struggling with early season velocity but it’s now headed up.

I’m encouraged with the rebound as it returns in 2018 levels

● James Paxton: While Paxton came into the season throwing as hard as he did in 2018, he’s decided to ramp up his velocity by over 1 mph in his last start. He’s had games like this in the past, so the key is to see monitor the next few starts.

● Martin Perez: The 28-year-old left was getting some preseason hype with his +95 mph fastball. His value took a hit when he started the season in the bullpen but he finally got a start. With that start, he averaged over 95 mph on his fastball and racked up five strikeouts in six innings of work allowing only one run.

The strikeouts are not a concern, but the walks are as seen by his weirdly nice 6.9 BB/9. He needs to drop this rate by a third to really jump up in the starter rankings. He’s on my roster-but-bench list of pitchers.

● Mike Fiers: He’s at the new velocity over the last two games but he’s allowed 12 Runs in 6.2 innings of work. Pass.

● Yu Darvish: He’s back to his 2018 fastball velocity but this was after the  “just throw hard” experiment. With all the changes, it’s tough to put an accurately set his talent level.

● Other notables with fastball velocities on the rise: Kirby Yates, Reynaldo Lopez, Aaron Sanchez, Carlos Rodon, Dereck Rodriguez, Jack Flaherty, and Chris Archer

Declining Fastballs
Name Pitch Velo Spin Count Zone% Velo Spin Count Injury
Hector Rondon FF 96.6 2079 46 44% 95.1 1979 8 -69
Mike Mayers FF 93.9 2331 71 46% 91.6 2303 9 -65
Jon Edwards FF 93.1 2438 48 36% 92.7 2348 12 -64
Ervin Santana FT 89.6 2033 14 47% 89.1 1981 9 -58
Ken Giles FF 96.7 2342 70 41% 96.2 2313 38 -51
Joey Lucchesi SI 90.7 2225 167 40% 90.0 2195 44 -46
Daniel Norris FF 90.2 2348 89 46% 89.0 2337 31 -45
Chad Green FF 94.8 2417 99 47% 94.7 2329 22 -44
Homer Bailey FT 93.1 2022 21 42% 92.4 2013 9 -44
Carlos Carrasco FF 93.1 2409 55 52% 91.5 2370 15 -43
Jakob Junis SI 91.0 1993 87 45% 90.2 1951 25 -42
Brad Brach FF 92.6 2222 75 35% 92.2 2176 17 -41
Corbin Burnes FF 94.6 2798 160 48% 94.7 2684 59 -40
Matt Grace SI 90.4 1814 77 36% 90.6 1777 9 -40
Zack Greinke FT 89.6 2168 19 45% 89.6 2031 7 -40
Adam Cimber FF 86.6 2191 12 49% 86.3 2175 6 -39
Joe Musgrove FF 91.1 2423 89 42% 91.0 2393 51 -39
Gerrit Cole FF 96.6 2515 203 52% 95.8 2453 53 -38
Joe Musgrove SI 89.9 2318 46 42% 89.8 2289 27 -38
David Hernandez FT 92.8 2223 21 44% 92.1 2170 10 -38
Drew VerHagen FT 92.8 2302 18 32% 92.6 2274 14 -38
Austin Brice FF 92.9 2264 25 46% 92.8 2199 11 -36
Adam Cimber SI 84.5 2131 42 49% 84.3 2106 22 -36
Chad Bettis FF 89.9 1975 77 52% 88.7 1969 32 -36
David Price FT 92.4 2217 74 48% 91.8 2195 33 -35
Nick Vincent FF 88.9 2367 65 54% 88.4 2334 31 -35
Corey Kluber SI 91.4 2241 113 43% 91.5 2122 20 -35
Ervin Santana FF 89.9 2070 83 47% 89.3 2041 37 -35
Giovanny Gallegos FF 93.7 2423 38 52% 93.7 2423 38 -35
Marcus Stroman FT 92.7 2301 144 42% 92.4 2242 44 -33

● Ken Giles: His fastball velocities have been all over the places to start this season.

If anything, the inconsistency worries me.

● Joey Lucchesi: Any decline in Lucchesi’s profile is discouraging. He’s just a two-pitch arm and a slower fastball could accelerate the decline.

● Daniel Norris: His velocity is heading straight down like it did last season before he went on the DL.

He is unrosterable at this point.

● Carlos Carrasco: His velocity dropped two starts ago but rebounded in his last start.

● Jacob Junis: He started the season with added velocity, but those gains have quickly disappeared.

● Corbin Burnes: He has a 0.5 mph drop from his first start. That doesn’t worry me as much as the 300-rpm decline. Usually, the ratio of velocity and spin (Bauer units) decline together but his spin fell more than expected in his last two starts.

We hoped you liked reading Changing Fastballs (4/18/19) by Jeff Zimmerman!

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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 three FSWA Awards including on for his MASH series. In his first two seasons in Tout Wars, he's won the H2H league and mixed auction league. Follow him on Twitter @jeffwzimmerman.

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SucramRenrut
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SucramRenrut

Sale for Greinke? Geez, I would rather have an injured Sale than a healthy Greinke at this point.