One of the ways we can cheat with the small sample sizes in the early part of the season is to look at velocity readings, since all starters have thrown a decent sample of fastballs.The problem though is that we are not comparing apples to apples, or rather Aprils to Aprils – at least not easily. What a guy is throwing now is most relevant only when you compare what he has thrown in prior Aprils. Cold weather has a small negative effect after the ball is thrown, only about 0.1 MPH with each 10-degree drop in temperature, according to physicist and must Twitter baseball follow Dr. Alan Nathan of the University of Illinois (@pobguy). But the cold has a less quantifiable effect on the limberness of pitchers’ muscles, we can assume. And some pitchers may just be slow starters, irrespective of the weather. There’s no reasonable way to precisely adjust for all these factors, but we at least can look at velocity splits by month. I’ve been keeping that for the last couple of years, for just this purpose. The problem is that I only have ERA qualifiers each year. So a guy like Chris Sale, who I am very concerned with given about a 2.5-mph drop from last April, does not make the list. (The other issue with Sale, an elbow-numbing slider rate of over 30 percent, perhaps will be a topic for another week.) Here are the noteworthy pitchers who stood out, sorted by the difference between their April 2013 velocity and the velocity they registered in April 2011 (though that was for all of April). Again, though, I only have ERA-title qualifiers as of April for 2011 and 2012. Weaver’s decline has been steady beginning last season. He finished 2012 slower and began 2013 slower still. I thought there was something clearly wrong with him physically and now maybe his broken non-throwing elbow will allow whatever that was to heal. But I wouldn’t get within 100 yards of Weaver until I saw proof of that. Righties can’t get away with throwing 85.5 mph, generally, and it’s much more concerning when we see his relative decline. If he was a Shaun Marcum-type who always operated with such subpar speed, okay. But that level of loss is shocking. You just never see anything approaching that unless the pitcher is old/injured. Verlander’s K/9 is down and his walks are up. Couple that with the extreme decline in velocity and you have to at least be wary. I’m not saying to trade Verlander. But he’s not holding it back for the big moments in games. His peak velocity this year is lower than ever, too. He hasn’t come close to hitting 100 mph. And the decline in peak velocity mirrors the decline in overall velocity almost exactly. This is significant enough for me to not trade for Verlander at his March 2013 price and to trade him if I could get that from an unsuspecting owner. Sabathia’s velocity decline concerns even him, though he’s apparently given up the effort to recapture what’s been lost. He’s getting by and has the advantage of being a lefty. He’s also dealt with this all of last year. So he’s perhaps better positioned to continue to make adjustments. The problem is figuring out when his loss of velocity reaches a tipping point that fundamentally alters his statistical profile. I believe we’re getting perilously close to that. Thus, for me, Sabathia is a strong sell. I don’t need any more reasons to broom James McDonald from my roster, but if you do, there it is, plain as day. Hernandez seems like he’s in a danger zone until we look at where he was last April and where he finished. So he seems to be a slow velocity starter, thus no change for King Felix. The thing I liked about Harrison always was his plus velocity for a lefty. That now seems to have steadily eroded. He’s also been uncharacteristically wild. Either can be a sign of injury. I’d stay far away from Harrison right now. The other decliners are out of the danger zone where they have lost more than two MPH, which is usually one grade higher or lower from scouts. Kuroda is 38 and commands the strike zone like the wiliest of veterans. I do not like Gallardo’s trend though. He was a power pitcher who now has minus velocity. Maybe that’s why he’s hitting the hooch. Jimenez seems a lot worse when you remember he was throwing 95 mph on average just a few seasons ago. He lacks the refinement to survive such declines. Garcia is on the list because we all were so worried about his shoulder. There is no evidence that this is an ongoing issue. Of course, that doesn’t necessarily mean it is not one. But Garcia should be confidently rostered in every format. Haren’s issues are clearly not velocity related. I do not take this to be good news, as there clearly are major issues. I don’t see any reason to have him active now anywhere, even in NL-only leagues. If you can reserve him while you wait to see if he can revert to 2011 form, fine. If not, don’t sweat cutting him. On the plus side, we have Shields, who I thought was going to be a big, fat bust this year removed from the Rays defensive-positioning, BABIP magic. Whoops! His 20 Ks against only three walks through April 17 suggests his ERA should be in the low 3.00s or better. And his spike in velocity suggests this level of excellence is sustainable given his outstanding changeup. Buy Shields.