Why Joba Won and Home Is Not So Sweet

Buster Olney's blog has a great section every morning where they break down why a certain pitcher won. From today:

Why Joba Chamberlain won, according to ESPN Stats & Analysis:
• He threw strikes 71% of the time, his best mark on the season(59% coming into the game, below the 62% MLB average).
• He worked inside, getting hitters to go 0-6 with four strikeouts on pitches inside.
• Braves hitters chased 44% of Chamberlain's pitches outside of the zone, much higher than his season average of 21%.

More than that Joba--and the rest of the pitchers--really don't seem to feel comfortable pitching at home as compared to on the road. They throw less strikes because they nibble and they end up getting behind batters and walking them. They're scared to throw inside to lefties because they know a little mistake will be jacked out into the "jet stream" of the New Yankee Stadium.

Here's a look at home/road splits:

• Joba Chamberlain
• Home - 0-2, 5.18 ERA, 21 BB to 36 SO, 9.82 K/9, 1.55 WHIP, 3 HRs in 33.0 innings, .246 BA/.738 OPS against
• Road -  4-0, 2.74 ERA, 16 BB to 33 SO, 6.96 K/9, 1.31 WHIP, 5 HRs in 42.2 innings, .255 BA/.755 OPS against
• CC Sabathia
• Home - 2-1, 3.99 ERA, 15 BB to 29 SO, 5.26 K/9, 1.15 WHIP, 4 HRs in 49.2 innings, .227 BA/.620 OPS against
• Road -  4-3, 3.44 ERA, 16 BB to 41 SO, 7.05 K/9, 1.13 WHIP, 4 HRs in 52.1 innings, .225 BA/.637 OPS against
• A.J. Burnett
• Home - 2-1, 3.91 ERA, 23 BB to 45 SO, 8.80 K/9, 1.43 WHIP, 7 HRs in 46.0 innings, .253 BA/.775 OPS against
• Road -  3-3, 4.61 ERA, 21 BB to 37 SO, 8.12 K/9, 1.44 WHIP, 6 HRs in 41.0 innings, .250 BA/.755 OPS against
• Andy Pettitte
• Home - 3-2, 5.77 ERA, 18 BB to 31 SO, 5.77 K/9, 1.76 WHIP, 9 HRs in 48.1 innings, .332 BA/.892 OPS against
• Road -  4-1, 2.35 ERA, 15 BB to 26 SO, 6.10 K/9, 1.15 WHIP, 2 HRs in 38.1 innings, .207 BA/.611 OPS against

So Pettitte is almost 3.5 runs better on the road, Joba is almost 2.5 runs better on the road, and Sabathia is half a run better on the road. A.J. Burnett is the real outlier here. He's actually pitched marginally better at home than on the road though his splits are pretty much even except for the 0.70 bump in ERA (which could be due to that stinker he threw against the Red Sox).

But the rest of the pitchers, not so much. Amazingly, everyone but Pettitte has a better OPS against at home, but the ERA jump is huge for Pettitte and Joba. Why is Joba's K/9 so much higher at home? Because I think he feels he needs to strikeout guys to win in that park. He nibbles around corners and gets into trouble with walks. Joba's batting average against is actually worse on the road, but the reason his WHIP is 0.24 higher at home is because he's afraid to let hitters put the ball in the air. Pettitte has a huge different in WHIP, HRs, BAA and OPS so you can see where his troubles lie. Sabathia has just had more success striking out guys on the road for some reason, a number he needs to fix.

While this explains some of the struggles of Joba and Pettitte especially, both guys need to learn how to pitch in their home park.

 

On a side note, the Yankees best OPS against at home is Brian Bruney (.333) followed by David Robertson (.464). I think it's time to give Robertson some more important outs. The Yankees best OPS against on the road is Brian Bruney (.322) followed by Mark Melancon (.350), albeit in small samples sizes. I think it's unfair to banish Melancon to the minors just because he couldn't get out of bases loaded in the rain against the Red Sox (at home, no less). He would certainly be a more intriguing arm out of that bullpen than Brett Tomko.