By Eno Sarris
"As soon as you're born you start dying; So you might as well have a good time." -- Cake, "Sheep Go to Heaven"
Here's a nasty open secret about pitching: Young pitchers don't get better as they age. There is no peak age. As soon as they start firing bullets they start running out of time. They're born and then they start dying.
Nothing is that simple, of course, but today's baseball is certainly working this way. We used to think that players peaked at 27-28, full stop. Now we're seeing that certain things -- like power -- might peak early, and other things -- like reach rate -- might peak later. It's complicated.
But among all these aging curves, there's the shared fact that baseball itself is changing. We'll leave the speculation about why to others, but it now looks like the peak baseball age is earlier than we previously thought. Even among hitters, there's evidence that there is no late-20s peak any more, and that hitters come into the league at their peak, stay there a while, and then start to decline. So maybe it's no surprise that the same is true for pitchers.
Look at these aging curves for pitchers, created by Bill Petti and Jeff Zimmerman at FanGraphs. The Y-axis shows year-to-year improvement in each stat. Pretty much all the good things plateau for a while and then decline, and all the bad things very barely improve before getting worse:
Notice specifically that for the events that are positive for pitchers -- strikeouts and swinging strikes -- their line never lives above zero. That means that, as a population, pitchers do not improve their strikeout rate as they get older. The best thing that you can say for a pitcher is that he might improve his walk rate a bit until he turns 31 (see the green line), but his overall performance (represented by FIP) won't generally improve.
That's because a main driver of performance for a pitcher is velocity, and the death of a pitcher's velocity is one thing we're sure of. Pitchers, as a group, do not gain gas as they get older. Watch that dashed blue line start with a gentle slope downwards before taking off for the basement after the pitcher turns 27.
One mile per hour of fastball velocity is worth a fifth to a third of a run of run prevention, Mike Fast found before the Houston Astros hired him away from writing. On average, even a 22-24 year old is already losing a half tick on the gun every year, and it's hard for a modest improvement in command to undo that loss.
Let's take a look at the pitchers that have lost the most this year. Just because we're into depressing things today, apparently.
|Name||Age||FB%||FBv 14||FBv 13||Diff|
There are some young players at the top of this list -- players like Robbie Ross, Martin Perez and Alex Wood -- that are younger than the traditional benchmark for peak baseball age, 27 years old. In the case of Chris Archer and Stephen Strasburg, maybe it's not such a big deal, since they started with plus velocity to begin with. For Dan Straily and Erasmo Ramirez, though, it might be a bigger deal.
Before we freak out too much, there are some caveats. Velocity peaks in August, and there's as much as a mile per hour that a pitcher can gain between now and then. But if they're down more than a mile per hour now, they'll still be down for the year once the averages are run. Most of these players will suffer in the final roundup, even if they've only pitched three or four games -- three games tells us almost all we need to know about future fastball velocity this season.
Of course, there are a few pitchers that have added velocity. Tyler Skaggs and Brandon McCarthy are the only two that have managed to add more than a tick and half on the gun, though, so it's not as if the two sides are balanced, and McCarthy underwent a heavy off-season regimen of lifting this offseason in order to increase his stamina. Skaggs revamped his mechanics with his trade back to the organization that drafted him. These are not things that our velocity losers can really attempt in-season, and they are also not effective for every pitcher the same way.
Other than to depress you about your favorite young pitcher, this realization can serve to give us insight into how teams approach pitching. Let's look at teams by average age and average fastball velocity to make the point clear. (Chart at right.)
Oh, look at that. The youngest teams have the fastest fast. Not surprising that we can find yet another way to fawn all over the Cardinals. But it is interesting to see other young teams following suit. The Marlins are Forever Young, the Rays don't sign free agent starters, and the Pirates, Cubs and Astros are building.
The Mets aren't quite there yet, and they did just sign one of the oldest starters in the big leagues, but it does seem like their plan to assemble young arms is following the path blazed by the Rays, Marlins and Cardinals -- when Matt Harvey, Zach Wheeler, Noah Syndergaard and Rafael Montero are all throwing gas in the rotation, there might be a different attitude in Queens.
It might not be fair to the Blue Jays to sort the list this way -- after all Mark Buehrle's 83 mph fastball is one of the slowest in baseball -- but this is the bed they made when they went after veteran starters. And since all of the injury projection work seems to suggest that age increases your chances of getting hurt, and that every pitch puts you closer to pain, this list has other implications. It's not by accident that the Blue Jays have the oldest rotation with the slowest fastballs and have also had the most pitching injuries over the past three years.
The implication seems clear: assemble as much young pitching as possible, and try not to spend too much money on free agent starters. Look at the Athletics, who consistently churn out young starters and then trade them for more young starters before their in-house options become too expensive. Tim Hudson, Rich Harden, Joe Blanton, Dan Haren, Gio Gonzalez, Trevor Cahill -- the list goes on. The idea, it seems, to let other teams deal with the lower velocity and higher injury risks.
Is it true that all pitchers just get worse? No, of course not. You could learn a new pitch, but that's easier said than done. After all, McCarthy has been searching for a change-up his whole career. Straily had to go through 17 grips to find his change-up. Tony Cingrani has heard from all of his coaches that he needs a better slider and is only now making progress. The list of players adding pitches in the spring is long, and the list of pitchers actually throwing those new pitches is short -- only Cingrani's slider, Stephen Strasburg's slider, Jake Odorizzi's splitter, Tom Wilhelmsen's cutter and Sean Doolittle's slider have turned into above-average pitches on that list.
Pitchers can also throw the fastball less as they get older -- they do, for what it's worth -- and resort to using more junk. That might be how CC Sabathia is now striking people out with one of the lowest fastball rates (and velocities) of his career. But, once again, it's the breaking stuff that's more often linked to injury, and you're still throwing a fastball at least 50 percent of the time. Even if you move to the two-seamer (like A.J. Burnett) or the cut fastball (like Dan Haren), you can't hide reduced velocity forever.
Generally, it's true: velocity is a huge part of why a pitcher is good, and velocity only goes down from year one. That's why the some of the best-run organizations in baseball focus on developing young arms. In a league where the average team uses ten starters over the course of the year, and every pitcher is already declining, it makes sense to accumulate as many young arms as possible. There is never enough.
Don't get too depressed about it. As Cake says in the quote that started us off, you might as well have a good time -- just go enjoy the next Yordano Ventura start. Snuggle up with a glass of something and Jose Fernandez on the tube. Get cozy with Gerrit Cole. Let your favorite baseball team worry about tomorrow's radar gun readings.
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Eno Sarris writes about baseball at FanGraphs www.fangraphs.com most of the time. He also started BeerGraphs www.beergraphs.com for the beer nerds out there. He doesn't always play daily fantasy, but when he does, he plays it at DraftStreet.com.