Continuing with yesterday's topic, except with red instead of green:

Would it be cheating to take Wakfield out of the sample?  His FB velocity clearly isn't as important as it is for a "normal" pitcher, as he only throws that pitch about 10% of the time.  This trend isn't new for him; here are his average FB velocities for every year FanGraphs has data (since 2002):

I'm not sure what was going on in '02 (he did spend half the year pitching out of the pen, although that's sort of a counterintuitive explanation), but since then the pattern is rather obvious. How much of a difference it makes isn't as clear. First of all, he's throwing it infrequently, so that will minimize the impact. But I also wonder how much of a difference there really is, to major league hitters, between 76 and 71. The latter has to be easier to hit, but there's no way that drop is as devastating to a pitcher as going from 92 to 87, even controlling for how frequently it's thrown. Regardless, Wakefield is certainly a special case.

Dave Cameron has documented Cabrera's somewhat confounding struggles. He's gone from an intriguing talent -- striking out almost a guy an inning in '05 while averaging 96 on the gun and posting a 4.02 FIP -- to completely useless, with a 1:1 K:BB ratio since the start of '09, and now a fastball that barely breaks 90. That, friends, is how you end up on the Nationals.

Perez's slow start has been well documented, which will happen when you begin the year with a 9.31 ERA in four starts after signing a $36MM contract. Interestingly, it's been a combination of a lack of velocity and far too many walks (15 in 19.1 IP) that's been the problem. It'd be interesting to see if Perez, who has a reputation for being "inconsistent", has had four starts where he's averaged 89mph in the past, or if this is the first time. It's also worth noting that last year he saw a bump to 91.2mph, after he was down around 90.4 in the two seasons prior.

Kazmir's numbers in the chart are down across the board, but it hasn't all been bad. After an outrageously low 31% GB% last year, he's back up to 43%, which is where he was from '05 to '07. He's also throwing his slider more (21% of the time, almost double last year's 10% but right around his career average), although he's lost almost 2mph there as well. The strikeout rate is definitely a concern, as is his questionable control. He's not exactly going down the Daniel Cabrera career path, but Kazmir has had a relatively rough time since striking out 239 guys in 206.2 innings as a 23-year old in '07.

Eveland had a nice season last year, although his 4.09 FIP was aided by a low HR/FB rate of 6.6%. His K:BB ratio has never been too impressive, but this year it's all the way down to one, which can mostly be blamed on his walk rate. While his FB is down from 90.1 to 88.3, he's maintained the velocity of his slider, which he throws almost 1/4 of the time.

In a few weeks I'll come back to this data and see how well FB velocity in the first three weeks predicts both velocity and performance in weeks 4-6. It also may be interesting, probably later in the season, to look at how many of the guys who have seen a dip in velocity end up on the DL.

All stats courtesy of FanGraphs.

Original Story: http://vegaswatch.net/2009/04/slowing...