Last week, the Seattle Mariners inked their ace, Felix Hernandez, to a $175 million extension for the next seven years. The dominating righty will be entering his age-27 season this year, meaning the contract will through his age-33 season. That is, unless, he injures his right elbow.
Embedded within Hernandez’s contract is a clause that gives the Mariners a club option for an eighth season — at a paltry $1 million — should Hernandez miss at least 130 consecutive days due to any kind of procedure to his right elbow. The Mariners negotiated this clause after some concern over what their doctors saw in the pitcher’s MRI.
Apparently, the club was reassured enough by their medical staff to sign the mammoth deal, even though the track record for long-term pitcher extensions isn’t the greatest. But how confident should the team be?
To begin with, Hernandez has been a starter in the league since 2005, and he moved into the rotation full time in 2006. Since 1920, Hernandez ranks 13th in innings pitched through the age-26 season. That list of 13 reads as you would expect — a group of historical hurlers — some of who continued their greatness after age 26 and others whose performances fell precipitously:
Here’s how each of those pitchers finished their careers after that:
Now, obviously these pitchers performed worse and provided less value than before age 27, and that’s to be expected. Only Catfish Hunter managed to see his adjusted ERA improve. Additionally, these pitchers saw their K% decline by roughly 3%, on average, and their HR/9 increase by .25. Another, admittedly crude, way to look at the decline is to compare WAR/100 IP. Here, 11 out of 12 pitchers declined, with only Catfish Hunter being slightly better (+.05).
These pitchers also saw their innings decline significantly. Eight out of the 12 pitchers saw their innings drop, relative to before age 26. Five of those eight experienced innings-pitched declines of at least 37%.
The Mariners are essentially betting Hernandez can give them an additional 28 WAR through age 33. A quick glance at this list tells us that only two pitchers with a similar workload by age 26 have managed to produce that much value — with a few coming close.
This is a long way of saying that, when we think of aging curves for pitchers, age is only one factor. We also need to keep in mind the amount of wear and tear pitchers experience and how that can dramatically impact how much “greatness” a pitcher has left — even for a player as young as Felix. And, to that point, there are some warnings signs for Hernandez: The biggest has to do with that right elbow.
Before reports of the questionable MRI and contract clause, there was reason for concern. Like most pitchers, Felix has seen his fastball velocity decline throughout his young career. That isn’t troubling. What is, though, is the rate at which that velocity has fallen.
Since PITCHf/x came online in 2007, Hernandez has seen his fastball velocity drop between 4 mph and 5 mph, depending on what data you look at. This applies to both his four-seam fastball and his sinker (which, according to Brooks Baseball, he throws significantly more often):
We know from previous research on velocity and pitcher aging that, on average, starting pitchers lose about .55 mph from their four-seam fastball between ages 21 and 26. Hernandez’s velocity loss is 10 times that amount. We also know that experiencing a velocity loss of at least 1 mph from one season to the next increases a pitcher’s odds of injury, further velocity loss and/or ineffectiveness. Hernandez has had such a decline four out of the past five seasons. Additionally, his sinker’s velocity declined between 1 and 1.5 mph in 2012.
However, while Hernandez lost velocity last year his overall velocity trend was more normal than 2011. Pitchers generally gain velocity as the season goes on. In 2011, Hernandez was essentially throwing his sinker the hardest early in April, only to see his velocity steadily decline through September (93.5 vs. 92.9 mph). Last year, Hernandez was only hitting a shade under 92 mph in April compared to 93 mph in September, more what we would expect.
That being said, let’s assume Felix’s sinker velocity will average about 92 mph in 2013. But how does that compare to other pitchers between 27 and 33 years old? Well, since 2007, we really don’t have a good comparison.
Based on our PITCHf/x data, of the 12 pitchers who rely on their sinkers at least 20% of the time, none throw it as hard as Felix is likely to next year. The closest comparison might be Adam Wainwright, who has thrown his sinker 26.7% of the time and averaged 90.6 mph. Since 2007, Wainwright has averaged a 75 ERA- and 77 FIP-. If we remove the age restriction, we find guys like Chris Carpenter (30.5%, 91.9 mph), Hiroki Kuroda (27.5%, 91.8 mph) and Derek Holland (21.3%, 92.9 mph).
Is Felix’s velocity decline troubling? Yes, given what we know about aging and velocity trends. But since Felix does not rely on his four-seamer as his primary pitch, the decline need not be as concerning as if it was happening to a different pitcher. Moreover, that Felix’s in-season velocity trend once again resembled a normal trend is a good sign. This year could be a critical one to determining how this extension will play out. If Felix can hold the line on his sinker’s velocity, it bodes well for his continued dominance. (In fact, his Steamer projection — which takes into account velocity — sees Felix posting a 5.4 WAR season in 2013.) However, if his sinker again declines significantly, it could further signal that Felix is aging at an accelerated rate — or worse, that his elbow in fact is not sound.
Bill leads Predictive Modeling and Data Science consulting at Gallup. In his free time, he writes for The Hardball Times, speaks about baseball research and analytics, has consulted for a Major League Baseball team, and has appeared on MLB Network's Clubhouse Confidential as well as several MLB-produced documentaries. He is also the creator of the baseballr package for the R programming language. Along with Jeff Zimmerman, he won the 2013 SABR Analytics Research Award for Contemporary Analysis. Follow him on Twitter @BillPetti.