Madison Bumgarner's Fastball is back and he could be Bumgarnering for a playoff team soon


The Giants’ new brass, led by Farhan Zaidi, made a gamble this past offseason. They chose not to trade their ace in the final year of his contract in the hopes that his performance in the early part of 2019 would raise his value to teams looking to bolster their staff before the playoffs. The Giants haven’t given anybody a good reason to follow them closely this season so you may not be aware of how this gamble has turned out for Farhan Zaidi. Or perhaps, you glanced at Bumgarner’s ERA(4.10) in the last few weeks and thought “oof, I bet Zaidi wishes he traded him in January.”

I’m here to argue, however, that there are reasons to think this plan hasn’t backfired and that Bumgarner might actually look appealing to a playoff contender based entirely on what he is doing on the mound right now; not playoff successes a half decade in the past. I’m not going to talk about his playoff track record because I don’t believe modern teams drastically alter their opinion of a player based on those things. I’m going to look at the things that modern teams care about: velocity, spin rate and an ability to generate whiffs.

This article centers on Madison Bumgarner’s fastball because that pitch was his bread and butter throughout his prime. According to Fangraphs’ Pitch Value metric his fastball was the 5th best fastball in baseball from 2013-2016(what I’m calling his prime). He never relied on elite velocity but sitting 92/93 was enough when paired with his command and pterodactyl-like delivery.


Age started chipping away at his velocity in 2016 and a dirt bike accident in 2017 removed a huge chunk of it. His ERA/FIP since the dirt bike accident is 3.51/4.02 which is a clear step down from the four seasons prior(2.86/3.06). The fastball is an easy culprit to look at. In 2017 and 2018 he was two ticks down from his 2015 fastball that averaged 92.9 MPH. It wasn’t just the velocity that showed his decline as his fastball also looked much worse according to Fangraphs’ Pitch Value. No longer an elite pitch it was a below average fastball in 2017 and 2018.

So what have I seen this year that makes me think teams actually want this declining pitcher? It starts with a tweet from long before the season started.


This picture shows me that the Giants are trying new things to make the most out of Bumgarner and that had me excited to see some positive changes in time for the 2019 trade deadline.


It’s now time to prove that Bumgarner’s fastball has returned. First up is a look at his velocity. In the chart below you’ll see his rolling velocity from all the way back to 2013. You’ll note the dirt bike accident in the early part of 2017 that really capped off the velocity decline he had already been experiencing.

5 game rolling velo.JPG

Look at what is going on in 2019 though. A huge spike since the beginning of the season. His fastball has average 92.7 MPH so far in May and that is the highest average velocity in a month since way back in August of 2015. To get a finer look at his recent velocity trend, here is a chart showing per game velocity in every start since the beginning of 2017.

single game velo.JPG

That’s three straight starts with a higher velocity than anything we’ve seen since before the dirt bike accident. Perhaps Bumgarner’s shoulder is finally healthy, allowing him to reach back in ways he hasn’t been able to in years.

I believe that fastball velocity is one of the first things teams look at when evaluating a veteran pitcher. A 29 year old with a declining fastball is a giant red flag to a GM but a 29 year old with a rejuvenated fastball is intriguing. Take the Astros acquiring Justin Verlander in 2017 as an example of a team seeing something in a pitcher’s velocity that intrigued them. Verlander was experiencing velocity decline and had lost 2 ticks off of his fastball in the seasons leading up to the trade. In 2017, however, his velocity returned to near prime levels but his performance otherwise was still questionable with an ERA/FIP of 3.82/4.07 at the time of the trade. The Astros made a bet on the velocity return and it paid off big time for them as Verlander was a true ace for them all the way through the playoffs.

Spin Rate

Aside from velocity, spin rate can be a great way to judge the “life” on a fastball. A high spin fastball is said to drop less on it’s way to the plate which can lead to more whiffs when thrown at the top of the zone. Sadly, spin rate is fairly new and we don’t have the data for all of his prime but you can see in the chart below that Bumgarner’s spin rate took a huge leap this season and may be the highest of his career.

spin rate.JPG

That spin rate number lands Bumgarner in the 87th percentile in baseball which is pretty impressive for someone whose fastball velocity(even after the 2019 jump) is only 10th percentile. This jump in spin rate could be a direct result of the Rhapsodo work that Bumgarner was doing in the offseason and may be the exact reason why Zaidi decided to wait to trade him.

Spin rate by itself may be intriguing enough to some teams that are looking at Bumgarner. We’ve seen in recent years that certain analytically inclined teams may be specifically hunting pitchers with high spin fastballs. Again, an Astros example(this time their acquisition of Charlie Morton) is the easiest to come to mind but teams like the Yankees, Dodgers and Brewers have put a noticeable emphasis on Spin Rate recently.


A fastball doesn’t have to get whiffs for it to be effective. In fact, fastballs generate fewer whiffs than any other pitch type. When Bumgarner’s fastball was at its peak, though, he got above average whiffs on it. Whiffs and his ability to get popups and weak fly balls were a huge part of why it was one of the best fastballs in baseball. Those things have gone away in recent years as his velocity and spin rate declined. Bumgarner went from a fastball that got more whiffs than normal to one that got less whiffs than normal.

But as can be expected with a rising spin rate and his velocity bump, his Swinging Strike Percentage on his fastball is back up.


Bumgarner's Swinging Strike Percentage on his FAstball by Season

The shape of this graph sure looks a lot like his velocity chart, doesn’t it?

To get a better look at how he’s getting better whiffs on his fastball I want to look at where he is locating the pitch. The following charts represent three different seasons of fastball locations. First is 2014 when his fastball was at it’s best. Next is last season when he had the worst fastball of his career. Finally this current season.


2014 Fastballs

2014 fastball locations.JPG

2018 Fastballs

2018 fastball locations.JPG

2019 Fastballs

2019 fastball location.JPG

The first thing to notice is how messy 2018 is compared to 2014 and 2019. In the zone and out of the zone he just seemed to have less feel for where his fastball was going. This season is back to a pretty refined and dialed-in gameplan with his fastball. The other key with these charts is the amount of fastballs he is throwing above the strikezone. This is where his whiffs are coming from. The extra spin and velocity are a perfect recipe for whiffs at the top of the zone.

Zooming out

Farhan Zaidi is still waiting to see if he made the right call on Bumgarner. He may be excited by what is happening with Bumgarner’s fastball and it alone should make Bumgarner a valuable trade deadline asset, but if he really wants some shiny prospects he’s going to need Bumgarner to start allowing fewer runs before the trade deadline. Thanfully for Zaidi, there are some more holistic signs that Bumgarner is better than what his current ERA is telling us.

plate discipline.JPG

A hallmark of Bumgarner’s prime was an elite K%-BB% that was a side-effect of the precise control he had over his multiple swing-and-miss pitches. Well so far in 2019 his K%-BB% is back inside the top 20 and it’s a big reason why his FIP and xFIP have bounced back as well.

All 3 of the attributes we’ve talked about on Bumgarner’s fastball(velocity, spin rate and swinging strike rate) lead me to believe that this pitch is once again a valuable weapon and combined with his overall improvement in key peripherals I think it’s clear his ERA should fall in the coming weeks. Just in time for Farhan Zaidi to make the first high-profile trade of his early Giants tenure.

Lucas Hooper