You can find more from Michael Salfino at SNYWhyGuys.com
I've been saying for years that velocity is a stat too overlooked by the sabermetrically inclined. Peripherals do have a tendency to follow it assuming the command is at a major league level. There are exceptions, of course, but it's generally true. So in this Pitching by the Numbers, let's focus on the radar-gun readings.
There are caveats this early beyond mere sample size. Cold air is more densely packed with molecules than hot air and we know that it decreases the distance of fly balls about one percent for every 10-degree drop in temperature. We should expect a similar effect on pitches thrown in the cold. So you may be able to discount declines of 1-to-2 mph if the pitcher in question has pitched in the cold.
Joe Nathan's(notes) dip is very concerning and not explained by anything other than a recovery from Tommy John surgery that's clearly not complete. Pre-surgery, he averaged 93.6 mph on his fastball and that was down about a mph off his post-2002 peak. Thus far, he's at 90.6 mph and he's throwing the pitch 48 percent of the time (62.8 percent for his career). The slider rate is 35.4 percent, as he tries to compensate. That's going to tax the elbow and may further delay a full recovery. I'd be trading out of these shares as soon as possible. Average time for a full recovery from Tommy John surgery is 18 months.
Edwin Jackson(notes) is down a couple of miles per hour. He was the poster boy for my velocity take back in 2009. Justin Verlander(notes) preceded him when his K/BB and K/IP lagged the elite radar gun numbers. This year, I similarly went all in on Clay Buchholz(notes) (not looking good after one start).
Note that Jackson has pitched in 39- and 44-degree weather. So his velocity normalized for more typical baseball weather is at least last year's number and maybe higher. More bothersome is that slider percentage number of 40.4 percent, far beyond the level at which the risk of arm injury rises significantly. Maybe it's an algorithm problem (pitches are classified by a computer based on movement and relative velocity parameters established by a programmer). But it scares me to the point where I'd be listening to offers if someone is now willing to give me a sixth-to-eighth round hitter.
Justin Verlander's declines should similarly be discounted for thermostat reasons.
More positively, his teammate Alexi Ogando(notes) is throwing at an elite pace for starters – 94.1 mph. But his slider percentage on Fangraphs is listed at 39.4 percent. His stay in the rotation will be short if that figure is correct. Definitely put his next start in your DVR queue and judge with your eyes because he can have mixed league relevance. Ogando is widely available in mixed leagues.
David Price(notes) is up 1.3 mph, so if there's any kind of discount from owners in your league worried about the Rays' ability to score runs, grab him. He'll peak at some point at over 10 Ks per nine innings and that could come at any time.
Clayton Kershaw(notes) is also up about a mile per hour, not that we need any other reason to own him. Of all the guys right now in baseball, Kershaw is probably the best bet to strike out 300, though the chances of that are small given modern innings/pitch count limits. Tim Lincecum(notes) is great but doesn't have the body to withstand the 260 innings he'll need. Kershaw – at 6-foot-3, 215 – does.
The reliever in the news this week is Jordan Walden(notes) and he has "closer" written all over him with that 96.5 mph fastball that he throws an eye-popping 84.1 percent of the time. Walden doesn't mess around, and why should he? This is not a short-term situation.
I must note that the Royals Jeremy Jeffress(notes) is averaging 97 mph. Joakim Soria(notes) is great, but has battled some shoulder issues. Jeffress is a former first round pick who has had a multitude of off-field problems. Still, he is playable at the moment in leagues with low innings limits and is the proverbial injury away from having significant value in all formats.
More pessimistically, we end where we started this year with Buchholz, who was down 2.0 mph in his first start in Texas, where it was 79 degrees. Monitor him this weekend against the Yankees. I'm assuming those 26.7 percent cutter numbers from his first start were actually sliders. That's over the 20 percent sliders max we can accept from our starters. Note that he wasn't credited with a single cutter in all of 2010.
Michael Salfino writes and edits the SNYWhyGuys blog that projects player and team performance for New Yorkers. He's also a quantative sports analyst whose writing regularly appears in the Wall Street Journal. .