The Curious Case of Brandon Pfaadt

We have Aaron Nola at home

Brandon Pfaadt is a fascinating pitcher to break down. Standing at 6’4 220 coming off a 32 start season, Brandon Pfaadt is as “prototypical starter” as it gets. Pfaadt struck out 185 hitters in 181.2 IP last season coming off a clutch and heroic 2023 playoff run.

Pfaadt looks the part, he’s flashed in the biggest moments…. but through 2 seasons and 50 starts, his career 5.06 ERA just isn’t good. Pfaadt now finds himself in a 3 way battle for the last spot in the rotation against $22.5M Jordan Montgomery and low key ace of the 2nd half of 2024, Ryne Nelson (the X account at discussbaseball pointed out from July 1st on in ‘24: 5-0, 1 SV, 82.2 IP, 3.05 ERA, 3.14 FIP, 8.71 K/9!)

The seat is hot for Brandon Pfaadt and there’s a real chance he ends up in AAA Reno to start the season…

But I don’t think that’s going to happen.

Every article I talk about how Jordan Montgomery needs to be traded and not gifted a rotation spot. Ryne Nelson makes a tremendous long reliever/6th starter when needed and I’m really high on Yilber Diaz and once healthy again, Cristian Mena (With Yu-Min Lin getting close too). Most importantly though, I think new pitching coach Brian Kaplan unlocks Brandon Pfaadt in 2025.

I liked Brent Strom, but I think when it comes to position coaches, you can just hit a development wall. A new voice was needed for the entire pitching staff and Brian Kaplan is a new age modern pitching coach. From the press release of hiring Kaplan, “Kaplan Co-founded of Cressey Sports Performance (Fla.), a highly regarded training facility for professional baseball players, including pitchers Max Scherzer, Justin Verlander and Corey Kluber and Devin Williams”. Kaplan from 2019-21 worked in the Phillies org, then 2022-24 was an on field assistant pitching coach. Per that same release, the 2024 Phillies starting pitchers ranked among the NL in BB/9.0 IP (1st, 2.49), groundball pct. (1st, 47.6), fWAR (2nd, 16.0), innings (2nd, 903.0), ERA (3rd, 3.81) and K/9.0 IP (5th, 8.48).

Kaplan has a strong resume, success and is ready to take over his own pitching staff. The biggest winner in my opinion of this hire is…. you guessed it… Brandon Pfaadt.

Why?

Brandon Pfaadt is about to become Aaron Nola.

From a straight eye test perspective, both guys have similar builds, similar mechanics and very a similar arsenal.

Nola:

Pfaadt:

Both guys throw their 4-seam fastball 27-33% of the time. Both guys throw their sinker 20-22% of the time. Both guys flash a changeup around 10% of the time. The big difference between them is their breaking ball.

Aaron Nola features a knuckle curveball, where Brandon Pfaadt throws a sweeper. Both guys use this pitch the same amount as their 4 seam fastball. Aaron Nola’s +12 pitch run value was one of the best figures in baseball…. as Pfaadt’s -10 was THE worst in baseball.

Shoutout Zac!

Ouch. But we also need to dig a little further under the hood here. Pfaadt’s sweeper was the ultimate boom or bust pitch last season. .195 expected BA (good), 36.2% whiff rate (good), but he threw the pitch A LOT and got beat BADLY when he did get beat. Last year (and click on name to see the HR replay) Arenado took the sweeper deep, Ryan Jeffers took the sweeper deep, and so did 11 other players….

At the same time, we do need remember the pitch has juice though.

So we sit here with this information. Brandon Pfaadt has better velo than Aaron Nola across the board. Both guys are extremely durable and have similar mechanics and pitch types, so circle back to Brian Kaplan, Aaron Nola’s old pitching coach to bridge this gap.

Brandon Pfaadt’s 2023 +8 run value on his sweeper actually beat Aaron Nola’s 2023 +0 run value on his knuckle curve. The tools are there and Brian Kaplan literally just fixed this same arsenal issue with Nola last season. Pitching development is a long journey and Brent Strom truly did fix Pfaadt’s 4 seam fastball issues from 2023 into 2024, now Kaplan needs to fix the hanging sweepers issue.

Here is where the game theory comes into play. Jordan Montgomery is gone next year no matter what, if not sooner. Ryne Nelson has already shown the ability to bounce between the bullpen and rotation. Brandon Pfaadt already gives a team a lot of value at his floor of being 32 start workhorse each season. Brandon Pfaadt also clearly has the “Aaron Nola” skillset and upside that is worth 7 years, $172M.

It’s worth noting that there’s a lot of other stats to show Brandon Pfaadt is much better than a 5 ERA guy. Let’s take a look at the advanced metrics:

xERA (expected ERA) Pfaadt 3.78 — Nola 3.71

K% Pfaadt 24.3% — Nola 24.0%

BB% Pfaadt 5.5% — Nola 6.1%

FIP (Fielder Independent Pitching on ERA Scale (neutralize bad defense for everyone) Pfaadt 3.61 — Nola 3.94

Hard Hit % Pfaadt 39.2% — Nola 38.4%

Average 4 seam fastball velocity Pfaadt 93.9 — Nola 92.6

How did both pitchers with insanely similar metrics have different seasons?

BABIP (BA on Ball in Play) Pfaadt .315 — Nola .294

Also, anyone who watched Pfaadt all season knows he had several starts where he was DOMINANT the entire game… besides 1 inning. Where Aaron Nola is about as steady and consistent as they come in the MLB. Nola is 31 and Pfaadt was 25 last season, and this hopefully another area Brian Kaplan and the new pitching staff can improve Pfaadt.

Watching Brandon Pfaadt highlights and some random Aaron Nola clips this offseason the connection clicked for me. Mix in Brian Kaplan from the Phillies and the fact that the two pitchers just throw really similarly, it’s crazy how close their seasons aligned the deeper you dive.

Brandon Pfaadt needs to be the SP5 on Opening Day, and while I think he will earn this job anyways, the Diamondbacks need to see the forest through the trees here. Pfaadt is just 26 and in year 3, you need to give him the opportunity to breakout with Brian Kaplan over trying to keep Jordan Montgomery happy.

Mike Hazen has pointed out often that he’s yet to have all 5 SP’s leave Spring Training healthy in his tenure, but regardless of injury, Brandon Pfaadt needs to be the SP5. The Diamondbacks have a long history of not being patient with young SP’s, don’t let Brandon Pfaadt join the list.

-Goldy Happens