SIERA Through 17 Games
Last year, Matt Swartz and Eric Seidman came up with a great pitching metric called SIERA, or Skill Interactive Earned Run Average. It is a lot like FIP and xFIP, but it specifically accounts for a pitcher’s batted ball skills, as well as his strikeout and walk rates. Last year, Roy Halladay led all of Major League Baseball in SIERA at 2.93, although that was significantly higher than his 2.44 ERA. Cliff Lee finished fourth; Cole Hamels 11th; and Roy Oswalt 14th. After the Phillies signed Lee in the off-season, I wrote, “The Phillies have one-third of baseball’s top-12 pitchers from 2010″ (at the time of the writing, Oswalt was 12th; there may have been slight tweaks in the Baseball Prospectus database that altered the rankings slightly).
The fearsome foursome could certainly make up one-third of baseball’s top-12 (or 14, if you’d prefer) in 2011 as well. It is still too early in the season to tell, though. In fact, Baseball Prospectus has not yet posted the 2011 SIERA leaderboard (here is last year’s). I, however, am curious and used my handy-dandy spreadsheet to take a quick look. Here are the inputs:
TBF: Total Batters Faced; SO: Strikeouts; BB: Walks; GB: Ground Balls; ofFB: Outfield Fly Balls; ifFB: Infield Fly Balls
The output, in SIERA, which is scaled to ERA:
- Halladay: 3.18
- Lee: 3.24
- Oswalt: 3.70
- Hamels: 3.13
- Blanton: 3.65
Perhaps surprisingly, Hamels has been the best of the bunch so far, contrary to his 4.32 ERA. He is the victim of a .367 BABIP, pitching quite well otherwise — getting a lot of swings and misses, being stingy with the free passes, and inducing a bunch of grounders. My Cy Young pick for the National League, Hamels is in for some regression in the BABIP department, but it should be slightly counter-balanced by his home run rate, as the lefty has yet to allow a round-tripper.
Least surprisingly, Halladay came within a hair of first place in the Phillies’ rotation, in terms of SIERA. Not quite the swing-and-miss maven, Halladay instead found success in rarely issuing walks and getting ground balls in bunches. He is the odds-on favorite to once again lead the Majors in SIERA. Should that happen, expect yet more hardware to appear on Halladay’s mantle in the off-season.
Lee rounds out a tightly-packed top-three. His strikeout and walk rates are better than Halladay’s, but lags behind in SIERA due to his sub-40 percent ground ball rate — roughly 13 percent lower than Halladay’s. He has been a bit BABIP-unlucky, so you should expect his 3.91 ERA to drop quite quickly.
Blanton ranks fourth, perhaps surprisingly. He has actually been quite good: his 7.3 K/9, 2.1 BB/9, and 54 percent ground ball rate are excellent, especially for a #5. Blanton is the most unlucky of the Phillies’ five, sitting with a .373 BABIP and the highest HR/FB rate on the team (13 percent).
Oswalt, who has recently been bothered by back problems, is in fifth. His strikeout and walk rates are good, as is his ground ball rate, but are not quite as good as that of Hamels, Halladay, and Lee when taken together. Additionally, Oswalt has been BABIP-lucky. His .240 BABIP should eke its way towards .300 in future starts, but it would be nice if Oswalt could continue his nice streak of luck that started when he joined the Phillies last season.
- Madson: 2.26
- Contrears: 2.53
Both have been great thus far. The Phillies are fortunate to have two extremely good arms pitching in most of the high-leverage innings.
Note: I used batted ball data from FanGraphs, which had not yet updated with information from Wednesday’s games. As such, I went into the play-by-play from yesterday’s afternoon match against the Milwaukee Brewers and interpreted the data myself. The data is subject to human error, which could be significant given the small sample sizes. If any errors are spotted, feel free to point them out in the comments.