Split personalities

When analyzing starting pitchers, there's never enough data. A full season will yield between 33 and 35 starts, which means you'll be making decisions during most of the season based on 25 or less starts. Throw in a DL stint (thank you, Chris Carpenter) and now we're talking 20 or less. For position players, 20 games is less than a month, which isn't enough to make decisions about hitters (anyone else have Julio Borbon down for 110 SB?). But with pitchers, we just take what we can get.

In order to make sense of the data and try to make it more useful, we also look at splits. How well does he pitch at home? How well does he do pitch during the day? How poorly does he do pitching to players whose last name is a palindrome (you'd be surprised what data I've looked at)? Of course, splits are more useful with more data. Now that we have almost five full months on our hard drives, let's take a look at some of the more interesting splits. Note that when a pitcher has bad numbers at night or good away numbers, I'm not saying to sit or start the pitcher always in that circumstance. It's just something to keep in mind in addition to other factors such as how he has been pitching lately, who is the opposing team and pitcher, and how many innings you have left.

Following are splits for 10 pitchers (5 AL, 5 NL) with some clues as to their identities. The answers follow on the next page. Good luck.

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1. "A Star is Born"Pre All-Star Break: 10-5, 3.04 ERA, WHIP 1.30, K/BB 2.40Post All-Star Break: 6-2, 1.29 ERA, WHIP 1.01, K/BB 5.40

This could be a Cy Young season for this pitcher. The once-promising youngster for the Atlanta Braves has hit his stride with his current team and has been unhittable the second half of the year, with his biggest asset being an increase in control. His overall K/BB for '09 is about where it was in '08, so don't hold your breath waiting for a fall to Earth. However, righties slug only .287 against him while lefties crush him at a rate of .413. The bottom line is he should sail the rest of the way, but beware the team stocked with lefty sluggers.

2. "Twilight"Day: 6 GS, 2-2, 3.79 ERA, 1.17 WHIP, SLG .429Night: 21 GS, 11-6, 1.92 ERA, 1.05 WHIP, SLG .327

This early season stud has cooled off as we know he would, but not as much as you think. His first and second half stats aren't that different, it's just that in the first half he had incredible months and very average ones. The second half he was been more consistent, and despite how bad his team is, a good argument can still be made for a Cy Young. However, not only does he pitch less well during the day, but he's been killed on turf (9.90 ERA vs. 1.90 ERA on grass). So just avoid those day games when his team travels to Minnesota, Tampa or Toronto.

3. "Indiana Jones"Pre All-Star Break: 1.23 WHIP, .319 SLG, 1.17 GO/AOPost All-Star Break: 1.48 WHIP, .419 SLG, 1.48 GO/AO

This pitcher's WHIP issues have been well documented in this column. While his walk rate has crept up, the plain fact is he's giving up more hits -- over two more per 9 innings -- in the second half and those hits are going for extra bases. However, he's the opposite of Pitcher No. 2, by being slightly better during the day (1.12 WHIP, 3.49 ERA) than at night (1.40 WHIP, 4.06). Even though he pitches in a pitcher's park, his road and home splits have been almost identical (3.84 ERA in 84.1 IP at home; 3.83 ERA in 82.1 IP on the road).

4. "Cirque du Freak"Home: 8-1, 1.83 ERA, GO/AO 1.59, .247 SLG, 0 HRAway: 5-3, 2.90 ERA, GO/AO 0.87, .335 SLG, 8 HR

We were ready to hand this pitcher another Cy Young at the break, but he has looked mortal in the second half. Actually, his numbers have been about the same in both halves of the season (2.33 ERA in the first half and 2.33 ERA in the second half), but he's had four no decisions out of nine starts since the All-Star Game. He'll see more success in September, but he's a victim of the heightened expectations for this third-year player. The miniscule home ERA makes the away one look much higher, but hey, you'd take a 2.90 road ERA from just about any starter. However, his problem on the road may be keeping ball up as his road GO/AO ratio is close to half of what it is at home (note that he's yet to give up a homer at home). For what it's worth, he has a losing record this year in day games (2-3, 3.00 ERA vs. 11-1, 2.03 ERA at night).

5. "Trading Places"TEAM A: 20 GS, 8-6, 2.94 ERA, 1.07 WHIP, .334 SLG, 11 HR in 133.0 IPTEAM B: 6 GS, 1-2, 6.82 ERA, 1.41 WHIP, .580 SLG, 11 HR in 37.0 IP

This lefty was a trade deadline acquisition for a contending team that he beat in his penultimate start for his old team. Pitching in a contract season, he has been terrible for his new team. Much to his new team's chagrin, he's already given up as many homers since the trade as he had before it. With his new team he's had three starts with one catcher behind the plate and three with the other, so that does not appear to be the cause. If Team B has any solace, it's that their rent-a-pitcher's failure has cost himself millions in what was probably going to be the last big contract for this 35 year old starter. Just be happy you have more power to bench him than Team B has.

6. "Home Alone"HOME: 3-3, 5.38 ERA, 1.63 WHIP, 5.25 BB9, 8.67 K9AWAY: 5-1, 3.15 ERA, 1.35 WHIP, 3.30 BB9, 6.60 K9

This Jonathan Winters look-alike followed a jubilant July (3-0, 2.73 ERA) with an awful August (1-2, 8.22 ERA), which might mean you'll find him on the waiver wire. Part of the problem may be fatigue from pitching more MLB innings this year than he did in the last two combined. It also may be the pressure of pitching for his team's fans in their expensive new green cathedral. Note that while his other numbers are worse at home than away, his K9 is better. This may be symptomatic of trying too hard to put away batters in more dramatic fashion, rather than relying on a groundball or popup. He'll likely be safe to use in September if the Yankees figure out how to handle him.

7. "The Color of Money"PRE ALL-STAR BREAK: 5-9. 5.01 ERA, 1.41 WHIPPOST ALL-STAR BREAK: 4-2, 1.92 ERA, 1.14 WHIP

If you look on your waiver wire you might find this high-paid lefty because no one is sure whether he's turned things around or not. He started the year 1-6 and has since gone 8-5. He's quietly been the catalyst that has put this team into Wild Card contention. In the second half his BB9 and H9 have gone down while his K9 has crept up, but none of these changes are dramatic enough to take credit for his renaissance. The real reasons have been better efficiency (17.00 P/IP in the first half vs. 15.40 P/IP in the second) and a counter-intuitive decrease in his groundballs (from 1.06 GO/AO in the first half to 0.74 GO/AO in the second). The latter stat bridges his success from his former team to his current one as his best days were when his GO/AO ratio was around 0.75. Pick him up, but beware the start against teams that bash lefties.

8. "Enemy Mine"VS. DIVISION TEAMS: 13 GS, 4-1, 6 ND, 16 HR, 5.62 ERAVS. ALL OTHERS: 13 GS, 10-4, 1 ND, 6 HR, 2.27 ERA

This hard-throwing SP1 already has two World Series rings, but if he keeps pitching like he has against his division foes, his team won't even get a Wild Card berth. His division stats are skewed by his last three games in which he gave up ten homers, and he appears to play for a manager that keeps trotting him out to the mound no matter how hard he gets hit. This pitcher, however, has historically had austere Augusts (14-16, 4.43 ERA) followed by super Septembers (18-8, 2.86 ERA). Don't be afraid to trot him out to the mound like his manager does and expect strong numbers the rest of the way.

9. "The Road Warrior"HOME: 3.77 ERA, 1.36 WHIP, 3.86 SLG, 0.84 GO/AOAWAY: 1.88 ERA, 1.04 WHIP, 3.49 SLG, 1.08 GO/AO

This Rookie of the Year candidate has been stellar no matter how you look at his splits, but his road numbers have been phenomenal. He plays in a hitter's park which accounts for the slightly higher slugging percentage against him. However, he has also getting less ground balls at home. His great work on the road has been a key factor in his team's crazy 41-23 road record (at .641, easily the MLB's best). Even though he hasn't been perfect in the second half of the season like he was in the first, he has actually pitched better (6-0, 2.90 ERA in first half; 4-3, 2.22 ERA in the second half).

10. "Do the Right Thing"VS. LEFTIES: 1.24 WHIP, .365 SLG, 2.10 GO/AO, 4 HR in 39.2 IPVS. RIGHTIES: 1.59 WHIP, .517 SLG, 1.30 GO/AO, 21 HR in 102.0 IP

These are the kind of numbers from which lefty middle relief specialists are born. This disparity, especially favoring the majority of MLB batters, is not tolerable for a starting pitcher on a first-place team. In the first half he was able to keep things together and went 8-5 with a 4.65 ERA. In the second half the wheels are coming off and he is 2-2 with a 7.67 ERA. He was on the DL for a couple of weeks and looked sharp in his first game back, but it remains to be seen if he can regain his form. Stay away from him this September.

Answers on next page...

1. Adam Wainwright (STL)

2. Zach Greinke (KC)

3. Chad Billingsley (LAD)

4. Tim Lincecum (SF)

5. Jarrod Washburn (DET)

6. Joba Chamberlain (NYY)

7. Barry Zito (SF)

8. Josh Beckett (BOS)

9. J.A. Happ (PHI)

10. Joe Saunders (LAA)

Hopefully that was as fun to read as it was to write. Just one more month to go. See you next week (likely a day or two later because of Labor Day) and have a safe holiday.