Affeldt: The Stars Aligned in 2009

On the heels of Jeremy Affeldt winning the Set-Up Man of the Year award, I decided to examine his season a little more closely. What I truly wanted to determine was whether not he could reasonably be expected to perform similarly in 2009. Unfortunately, he cannot. I’ve mentioned before that it’s extremely difficult for a batter to consistently beat the average of a BABIP (Batting average on balls in play) because they have little control over what happens once the ball is actually put into play. Have you ever heard a play-by-play guy say, “It’ll look like a line drive in the box score tomorrow?” They may not know it but they are talking about the luck that is involved in baseball. I also mentioned that the BABIP works for pitchers as well (though there are always exceptions, and Tom Glavine was one), and as it turns out, it’s even more useful for evaluating the future performance of a pitcher. So too is something called FIP. FIP was researched by a very smart baseball man named Voros McCracken. Voros believed that a pitcher can only control three main things, homeruns, walks and strikeouts. It’s essentially the exact same principle used with BABIP. To prove this he created an equation called FIP. The basic equation is:
FIP = ((13 x HR) + (3 x BB) – (2 x K))/IP

*HR = Homerun, BB = Walk, K = Strikeout, IP = Innings Pitched
FIP is an indicator of how well a pitcher pitched, independent of how well his fielders fielded. You probably won’t be too surprised to know that both Zack Greinke and Tim Lincecum both had excellent FIP’s in 2009. If baseball was fair and luck was not a factor (in market terms, if it were efficient) then FIP would essentially mirror ERA. But, baseball, like life and the market, isn’t fair (it’s inefficient) and FIP doesn’t always mirror ERA. Both Tim Lincecum and Greinke had higher ERA’s than were their FIP’s in ‘09. In 2008, Lincecum hit both dead on, i.e. you could say he was luckless. His FIP 2.62, his ERA 2.62. This is rare. In 2009, his ERA was 2.48, his FIP 2.34. So you could say he was just slightly unlucky. Also, in 2009 his BABIP was .292 while in 2008 it was .313. If he got some extra luck (say in the range of a .265 to .275 BABIP), you can only imagine how that might positively impact (lower) his ERA. Luckily for the Giants in 2009, Affeldt got a nice chunk of this so called luck. A really nice chuck. And unfortunately, Affeldt and Giants fans will more than likely be staring at a sharp regression for their shiny new set-up man.

When looking at 2009, you can see that Affeldt had a .244 BABIP. The average BABIP for a pitcher is right around .285. Throughout his career (and even including the anomaly of 2009 in the average) his BABIP has been .306. Even more unsettling is the difference between his ERA and his FIP. Affeldt’s ERA in 2009 is 1.73 while his FIP is 3.59! His ERA is actually more than twice as good as his FIP. Notice also how his career FIP and ERA are almost equal. That’s not surprising because we know that when it rains it pours and when you’re on a roll nothing can go wrong, but eventually it evens out. They are near the same because over a larger sample the truth really comes out. You can also see that his LOB (Left on base percentage) in much higher than it had been throughout his career. It will be incredibly difficult to sustain that as well and really is just a byproduct of being so lucky and giving up fewer hits than he normally would have and probably should have. What he did do well which helped his overall numbers was limit the HR. Affeldt does have the ability to control this, and thus this is commendable. You’ll also notice that in 2008 his BB/9 (Walks per 9 Innings Pitched) was 2.87 which is much lower than his career average. In 2009 he was back to his old tricks and walking about 4.5 per 9 IP. But because Affeldt had so much success when the ball was put into play and stranded so many runners, he was not hurt by them. If you are a Giants fans, you may or may not recall how many double plays he induced. He induced a ton. This is particularly peculiar because Edgar Renteria is no Ozzie Smith, especially at his age. Affeldt induced nearly 20 though he pitched fewer than 70 innings. Now take a look at his GB/FB (Ground Balls / Fly Balls) for 2009. Throughout his career, he generally was getting about 1.5 ground balls for every fly ball; however, in 2009 he had 3.5 batters hit ground balls per every 1 fly ball. Isn’t that strange?

I used the wonderful fangraphs.com to come pull together all of these stats, and stumbled across this which explains this phenomenon perfectly. I wasn’t the first to unearth Affeldt’s shocking secret. This was posted back in July of 2009. Affeldt magically got a ton of ground balls in 2009 that he hadn’t historically gotten. There seemingly was no fundamental reason for it, either. He is not a sinker baller pitcher, like Derek Lowe, who throws a heavy ball that makes batters pound the ball into the ground. He primarily throws a 4 seam fastball that usually results in many more fly balls and a very nasty curve ball. Mike Krukow has said that Affeldt has come to believe he can control his curve as well as his fastball. If he is throwing that curve more often now than he had in the past, and players aren’t expecting it, and if we’re lucky, that curve he is throwing is the reason for all this grounder madness. But it’s not. Affeldt has thrown roughly the exact same percentage of fastballs and curveballs over the last 3 seasons. So the only hope now is that his fastball got way better, his curve got way better, or a combination of both. Again, unlikely.

So now that we know that all of the stars aligned for Affeldt for one magical season in 2009, we should realistically expect him to come back down to earth. His BABIP will likely go back up to his career average (about .300 at least). Even if he continues to allow fewer HR than he has historically (and AT&T should help him with this), and walks fewer than he did last year, he will still likely give up more hits and more runs in 2010 which will significantly increase his ERA. I’ll be willing to bet that his ERA will be between 3 and 4 in 2010, which isn’t such a bad thing and he’s still a pretty decent reliever. He’s just not that good of a reliever.
It’s almost Christmas so I won’t give you a big old lump of coal and nothing else. There is a silver lining in all of this and his name is Dan Runzler. The Giants have a nice collection of young, solid and quality relief pitchers. Runzler no doubt sticks out in my mind. In the very few appearances I’ve seen him he has a very nasty slider and appears to have nice control. Also, he is left handed with a very easy 93-96 MPH fastball. Even with a fringy second pitch, he could probably be a serviceable left handed arm in the bullpen if he’s able to locate that plus fastball. And this is good because Affeldt was the only left handed reliever the Giants employed for most of 2009, and we know he won’t quite cut the mustard next season. At least not like last year.