Room for the Starting Rotation to Improve?
Phillies starters have the second highest babip in the majors
And it’s true! Via Baseball Reference:
The breakdown by starter:
The Phillies’ staff as a whole allows the fourth-fewest line drives in baseball (17.4 percent) and gives up hits on them at nearly the National League average (72.1 percent to the NL’s 71.4 percent). They also allow the fifth-fewest fly balls (34.2 percent) as well and give up hits on those at exactly the NL average (13.8 percent).
By the process of elimination, or sheer knowledge of the staff, you may be able to deduce that Phillies pitchers must induce a lot of ground balls. They do, at the third-highest clip in the Majors (48 percent). Those have not been converted into outs at a 27 percent rate, 3.4 percent above the NL average. With 723 ground balls induced, the additional 3.4 percent accounts for about 25 hits, or roughly 13 percent of the 195 total ground ball hits.
Using the current distribution on ground ball hits (93 percent singles, seven percent doubles), and the linear weights assigned to events in wOBA, we can get a general idea of how harmful the below-average conversion of ground balls into outs has been so far.
(.93 * 25) = 23 singles, (.07 * 25) = 2 doubles
(23 * .77) = 18 runs for singles, (2 * 1.08) = 2 runs for doubles; 20 runs total (or roughly two wins)
Is the culprit just bad luck? The Phillies have the third-worst defensive efficiency in the Majors at .698. They also have the ninth-worst UZR at -8.2. Looking at specific players reveals that only the second basemen (Wilson Valdez, Pete Orr, Chase Utley) have been harmful defensively among the infielders. The trio combine for a -3.6 UZR which is negated by Placido Polanco (+3.5), Ryan Howard (+0.1), and Jimmy Rollins (0.0). So, no, the infield is not truly to blame.
So, let’s take a look at Phillies’ pitchers’ BABIP on ground balls.
Remember, the NL average is .236, so everyone but Kendrick and Worley has been unfortunate in this regard. Halladay, Lee, Blanton (if and when he returns), and Oswalt should not be this unlucky on grounders going forward. That means that tweets like this and this should become more and more infrequent. In combination with this information and comparing their ERA to your retrodictor of choice (mine is SIERA), we can set our expectations for the rotation going forward.
- Halladay: 2.56 ERA / 2.66 SIERA
- Lee: 3.94 ERA / 2.81 SIERA
- Hamels: 3.01 ERA / 2.62 SIERA
- Oswalt: 2.70 ERA / 4.13 SIERA
In the big picture, Hamels should continue to be great, Halladay should improve slightly, Lee should improve greatly (assuming his cutter isn’t a problem, which would run contrary to many popular theories floating around), and Oswalt should get a bit worse despite BABIP regression as his strikeout rate is way down. Assuming Kendrick doesn’t make two to three complete disaster starts, the Phillies rotation appears to have better things in store as the 2011 season moves along.