For years now, Tom Verducci has studied the workload placed on young starters, and how dramatic increases in workload can lead to injury. As most baseball fans know by now, Verducci’s research claims that starters under age 25 are more prone to injury if they exceed their previous year’s innings total by over 30. Each year he identifies the young starters who took the biggest jump in workload and places them under the spotlight. Last year we saw Dustin McGowan go down with a season-ending rotator cuff injury.
Verducci leads off this year’s selection with a conversation he had with Mike Pelfrey, who apparently is familiar with Verducci’s theory (or what he terms a “rule of thumb”). With a 48-inning jump from 2007 to 2008, the Mets right-hander was a shoe-in for this year’s list. Yet he doesn’t think he’s going to fall victim like so many have in the past. Working in his favor, he believes, are his age, 25, and his size, 6’7″. Verducci responds:
“You’ve got a point,” I told him. After all, the dude is big. “I believe the bigger your frame and the older you are — guys near 25 are different from a guy who is 21 — can be mitigating circumstances. They probably put you at less risk — but still at risk.”
“I threw 140 innings at Wichita State — in three months,” Pelfrey said.
“Good point,” I said. “That’s still not 200.”
“The other thing is I bet I went through a lot more stress in 2007 than I did last year,” Pelfrey said. “It seemed like I constantly had runners on in 2007, and I really worked to improve my efficiency. So I might have thrown more innings, but I didn’t have all those innings with runners on base and high pitch counts.”
The last paragraph is the really interesting one. Innings are an inexact measure of workload. No number can give you a real look at a pitcher’s workload — not innings, not pitches, not even Baseball Prospectus’s Pitcher Abuse Points. Pitches and innings surely play a part, but when factors like when the pitches were thrown and how many of them were thrown at once come into play, you get a different picture of a pitcher’s stress level.
Jeff at Lookout Landing covered this a couple of years ago when the Mariners wanted to take this approach with Felix Hernandez:
It’s exactly how a young pitcher should be treated. Counting innings is what’s silly; 200 frames for Gil Meche are way different than 200 frames for, say, Roy Halladay, and the total barely even gives you an approximation of workload and stress level. It’s something of a barometer, since a guy with 100 innings will generally have less wear and tear than someone with twice as many, but it’s incredibly inefficient, to the point where it’s not even worth monitoring when there are better alternatives available. Which there are.
Innings sometimes provide a ballpark estimate, but pitch context and mechanical consistency tell you much much more. If Pitcher A throws 90 pitches and allows ten baserunners in five innings, while Pitcher B throws 110 pitches and allows six baserunners in seven innings, Pitcher A’s going to be doing more damage to himself, since he’s working in more stressful situations. That’s what wears a guy out and puts him at risk for injury – having to focus on every individual pitch with men on is way more tiring than cruising through the bottom of the order with the bases empty. That much we know. So why not account for it when you’re keeping track of a young pitcher’s progress?
I’m sure many teams employ these methods to ensure the health of their young pitchers. The Red Sox are known for administering strength tests throughout the season to make sure their players aren’t breaking down. Apparently Jon Lester, who tops the 2009 Verducci list with an 83.1 inning increase, passed all of his tests last year, so this will be an interesting study. If Lester holds up, you can bet a few more teams will implement a system like the Sox.
Other notables on the list include Cole Hamels, who pitched 79 more innings than in 2007. Hamels had elbow trouble this spring and missed his Opening Day start, though he won’t go on the DL. The NL Cy Young winner Tim Lincecum is No. 4 with a 49.2 inning increase.
While not an infallible rule, Verducci does note his success in the recent past. Over the past three seasons he’s identified 24 pitchers he’s considered at-risk. Of them 16 were hurt in the season he identified. Further, only one both avoided injury and saw a lower ERA in the Verducci season (Ubaldo Jimenez of the Rockies, for anyone interested). So while some might complain that the Yankees are babying Joba Chamberlain with his innings limit, it’s in place for good reason.
It comes as a relief that no Yankees made this list this year. Ian Kennedy did make it last year, and as we saw he went down with an injury, though it’s tough to say whether it had anything to do with his innings increase. You know what they say about correlation and causation.