Monday, August 14, 2006

Of Wang and Workloads

Before 2006, Chien-Ming Wang had never thrown more than 150 innings. That mark was set last year, when he missed a good portion of the season due to a freak rotator cuff injury. Right now, he’s at 166.1 innings, and it’s starting to show. The imminent question: is this a sign of things to come for the rest of ’06?

Allow me to quote someone with a bit more expertise in this field. From Baseball Prospectus’s Will Carroll (talking about Scott Kazmir, also in his second year):

He's testing the 130-inning hurdle, one of the four landmarks for seasonal fatigue. They start at 100 innings, then every 30 additional innings. Research has shown that the ability to "clear" one of the hurdles for the second time shows an ability to consistently hit that level.


Wang pitched 125 innings in 2003, 149.1 innings in 2004, and 150.1 innings in 2005 before his 166.1 so far this year. He’s hit the second hurdle, but for only the first year. Unfortunately, I haven’t been able to find any further literature about these "landmarks for seasonal fatigue," so what follows is in accordance with my interpretation, based on this theory and other innings-based pitching theories.

[MORE]While Wang may have the experience of a second-year player, he basically has the arm endurance of a rookie. The main difference between rookie and veteran pitchers is the length of season. Most minor leaguers are limited to somewhere around 150 innings max for a season. So when they get to the Major League level, the extra month-plus workload makes them more susceptible to fatigue and injury.

For an example of this in motion, I’ll point to one of the phenom rookie pitchers this year, Justin Verlander. Since Verlander pitched only one year in the minor leagues, I’m going to stretch back to his college numbers.

Year20022003200420052006
IP113.0116.1105.2130.0140.0


Verlander hit his innings mark from last year during a 6.2-inning, eight-strikeout performance against Cleveland on July 26. His next start, on five days rest, was against Tampa Bay on August 1, where he allowed three runs on eight hits through five innings. The main reason for his removal was his pitch count, 91. Three days later, it was announced that Verlander would miss his next start. Nothing seemed wrong, just a precautionary measure due to his lack of experience.

"I'm definitely not hurting. You can nix that one. Obviously, there was a little fatigue that I felt last time out, so to be on the precautionary side, I get a start off.

"But to be honest, this is the best I've felt after a start in a while."


That quote seemed innocent at the time, but became suspect when Verlander, on nine days rest, got bombed by the White Sox on Friday, to the tune of 13 hits, five runs (four earned), and two home runs over five innings (98 pitches). The Tigers now face a major question in their pennant run: can they rely on Verlander down the stretch with so many innings already under his belt? This will probably manifest itself during Verlander’s next scheduled start, which would be Wednesday at Fenway, barring a further setback. Another weak outing could mean some extended time off for the 23-year-old.

The question is, are these situations comparable?

Year20022003200420052006
Verlander113.0116.1105.2130.0140.0
Wang78.1125.0149.1150.1166.1


Wang has consistently pitched more innings than Verlander, which at first glance doesn’t make the situations line up. However, they both demonstrated a drop-off when they reached their personal highs in innings pitched (both attained in 2005). The Tigers are making the right move by trying to give Verlander more rest. Unfortunately, that isn’t a viable option for the Yankees, who have no real adequate backup plans.

Let’s place this against a larger sample, Wang’s 2005 rookie pitcher class.

Year20022003200420052006
C. Wang78.1125.0149.1150.1166.1
F. Hernandez-69.0149.1172.1136.1
S. Kazmir18.0109.1134.1186.0128.2
Z. Duke60.0141.2148.1192.2143.0
E. Santana-154.143.2192.0147.1
D. Haren*193.2173.1174.0217.0161.2
G. Chacin119.269.1167.1203.251.1
*not technically a rookie, but the first year he pitched the bulk of his innings in the majors

Chacin has been mired with injury this year, which becomes more understandable when you look at his innings totals. Before the 119.2 innings in 2002, he had tossed 132 and 140 innings. This is quite the workload for a young pitcher (his age 19 and 20 seasons), especially at the start of a career (he pitched 64 innings in rookie ball the year before his 132-inning stint). The 2003 injury and subsequent drastic workload increase is probably the reason he’s having trouble staying healthy this year. It speaks volumes about the proper care of young pitchers (I’ll get to this with Phil Hughes in just a second).

Beyond that, it seems that most of these pitchers were properly worked in their respective farm systems. They are also well positioned at this point in the season; almost everyone is well below last year’s total except our good friend Wang. The only pitcher that comes close to him as far as IP for 2006 is Dan Haren, and his situation is more understandable, since he’s handled heavier workloads in the past.

So have the Yankees done a poor job in managing Wang this season? Looking at his peers, it would appear so. It is possible that his workload has been the result of consequence (i.e. the absence of $40 million dollar man Carl Pavano), leaving the Yankees with little beyond the option of pitching him normally and hoping there isn’t any negative result.

Just for kicks, let’s look at some 2003 rookies and their innings pitched loads in the subsequent years:

Year20012002200320042005
J. Bonderman-156.2162.0184.0189.0
R. Harden74.1153.1176.1194.2131.0*
C. Lee-156.0132.0179.0202.0
B. Webb162.1159.0198.2208.0229.0
D. Willis93.2157.2197.0197.0236.1
* injury season.

It appears that Wang hasn’t been nurtured like the rest of these arms. What it actually proves is up for debate, but I think it speaks to the development of young pitching and how their workloads need to be carefully monitored. These players were properly and incrementally worked harder each year, and are finding much success in the Major Leagues. It doesn’t make me any more confident about Wang.

Post-Script:

With this information in hand, let’s look at how the Yankees are handling Phil Hughes.

Year200420052006
IP5.086.1131.0


He’ll likely have three more starts this year (by the way, killer outing yesterday, 5 innings, 9 Ks, 2 BB, 0 ER), putting him at roughly 146 innings for the year. The idea next year would be to get him up to 160-170 innings, so that he’ll have a chance to hit 200 for 2008, which would likely be his rookie season. There is always the chance of his arrival in 2007, but due to his limited experience and workload, it may be more beneficial in the long term to keep him in Columbus. That is, unless he utterly dominates opponents in AAA. He’d just have to be closely monitored in the bigs, and would likely be a spot starter. The point is, though, that the Yankees are doing a good job of keeping his innings in check, positioning him better for future success.

Stats obtained from The Baseball Cube