A few weeks ago, I introduced True Season Score, an update on last year’s Season Score. If you haven’t been following, Season Score attempted to evaluate a pitcher’s cumulative success at any point in a season by accumulating his Game Scores and adjusting for replacement level. True Season Score (TSS) changes the Game Score formula to focus more on true outcomes (walks, strikeouts, and home runs), while placing a lower value on fielding- and context-dependent outcomes like hits and runs.
Coming into the season, one would have expected the Phillies to stand head and shoulders above the field in team True Season Score (as they did last year), with the Angels, Giants, Rangers, and Rays jockeying for second. The Nationals, Yankees, Brewers, and Tigers were intriguing as well, and all would have made the top ten had I made predictions prior to the season. Two months into the season, most starting pitchers have made at least ten starts, with a few front-of-the-rotation guys making as many as 12. As we did last June, let’s see what teams have the best one, two, three, four, and five starters at this point in the season.
Best One Starter
Tigers (Justin Verlander), 177
No surprise here. Verlander leads the AL with a 2.31 FIP, and is a third of an inning behind league leader Felix Hernandez in innings pitched, despite having made one fewer start than King Felix. Verlander’s 177 TSS leads all of baseball by 26 points and leads the AL by 48. The Giants (Matt Cain, 151) and Phillies (Cole Hamels, 134) are second and third, respectively.
Best Two Starters
Giants (Matt Cain, Madison Bumgarner), 243
Nominal Giants ace Tim Lincecum doesn’t even factor into this exercise, as his -19 TSS isn’t enough to place him among the Giants’ five best starters. Nevertheless, Cain and Bumgarner have been dominant as expected, accumulating Season Scores of 151 and 92, respectively. Cain is striking out a near-career-high 8.32 batters per nine and walking a career-low 1.71 and still outperforming his FIP. Bumgarner has quietly maintained an ERA near 3, primarily by limiting walks (1.70 per nine).
Similar to the Giants, the Phillies are in second place behind their secondary and tertiary aces, Hamels and Cliff Lee (who hasn’t been credited with a “win” despite 57 innings with a 2.68 xFIP) and their 232 combined TSS. The Nationals (Gio Gonzalez and Stephen Strasburg) are third.
Best Three Starters
Phillies (Hamels, Lee, and Roy Halladay) and Nationals (Gonzalez, Strasburg, and Edwin Jackson), 316
Philadelphia would almost certainly lead this category alone if Roy Halladay hadn’t gone on the DL last week, but let’s give credit to the Nationals, whose three best starters rank 3rd, 9th, and 13th in the NL in TSS and 1st, 3rd, and 17th in FIP. Gonzalez and Strasburg have combined to strike out more than 11 batters per nine. No other NL pitcher has struck out as many as ten.
The Giants are third on this list, adding Ryan Vogelsong’s 71 TSS (and 2.36 ERA) to Cain’s and Bumgarner’s dominance.
Best Four Starters
Nationals (Gonzalez, Strasburg, Jackson, and Jordan Zimmermann), 392
Here’s where the Nationals really take off. Zimmermann’s been a little bit smoke-and-mirrors, his 2.80 ERA belying his 3.68 FIP, but he doesn’t walk anybody (1.54 per nine), and has a track record of striking out more than the 6.16 per nine he’s struck out so far. If he gets going, this may truly be the best rotation in the game.
Vance Worley’s 42 TSS puts the Phillies second in this contest, with the Angels (Jered Weaver, Dan Haren, CJ Wilson, and the surprising Jerome Williams) sharing the load rather democratically to stand in third.
Best Five Starters
Nationals (Gonzalez, Strasburg, Jackson, Zimmermann, and Ross Detwiler), 399
This isn’t exactly a “best rotation” competition, since many regular starters have negative True Season Scores, which means they may be replaced by a spot starter who has had some success in limited action among a team’s “best five”, but that’s not to say the Nationals don’t deserve this title. They’ve only needed one start from anyone outside their opening day rotation, and all five starters have been good, including Detwiler, whose 3.73 ERA and 3.54 FIP are above replacement level (most teams don’t have five starters above replacement level so far).
The Philies are just five points back in this race, as Kyle Kendrick has pitched effectively in the fifth spot for them. Consider the disparity in starts (the Nationals’ five best starters have made 50; the Phils 44 (47 if we count Joe Blanton, rather than Kendrick, among their five best) and it’s likely that the Phillies, when healthy, still have baseball’s best rotation.
The Angels are third here behind a resurgent Ervin Santana, who’s back above replacement level with a TSS of 5.
Aside from Verlander and the Angels, we haven’t seen any American League teams on this list, and wouldn’t even if I listed the top seven five-man rotations. The disparity in offensive environments between the two leagues is even bigger this year than in the past, with potent offenses in Texas, Boston, and elsewhere propping up the AL, while the rotations cited above have shut down hitters in the NL. The second-best rotation in the American League has been the White Sox, with Jake Peavy (129), Chris Sale (102), Gavin Floyd (13), Jose Quintana (5), and Philip Humber (3) all pitching adequately.
The best rotation we haven’t mentioned is the Mets, with RA Dickey (115), Johan Santana (106), Dillon Gee (29), Mike Pelfrey (23), and Jonathon Niese (5) all decent so far.
For the record, here are the ten best five-man rotations in baseball, with total TSS and runs allowed:
1. Nationals (Gonzalez/Strasburg/Jackson/Zimmermann/Detwiler), 399, 167
2. Phillies (Hamels/Lee/Halladay/Worley/Kendrick), 394, 220
3. Angels (Weaver/Haren/Wilson/Williams/Santana), 348, 195
4. Giants (Cain/Bumgarner/Vogelsong/Zito/Hacker), 323, 206
5. Mets (Dickey/Santana/Gee/Pelfrey/Niese), 278, 244
6. Marlins (Sanchez/Zambrano/Buehrle/Zambrano/Johnson), 274, 212
7. Dodgers (Kershaw/Capuano/Lilly/Harang/Eovaldi), 264, 196
8. White Sox (Peavy/Sale/Floyd/Quintana/Humber), 252, 217
9. Rays (Price/Shields/Hellickson/Niemann/Cobb), 221, 208
10. Tigers (Verlander/Smyly/Fister/Scherzer/Porcello), 208, 242
No matter how we slice it, the team with the worst rotation has been the Rockies, whose “best” starter has been Josh Outman, who racked up an adjusted True Game Score of 15 in his only start of the year. Their best regular starter, Juan Nicasio, has a negative 21 TSS and a 5.28 ERA. Nicasio hasn’t been all bad, and Christian Friedrich looks promising, but the team has a combined TSS of -214, which suggests that the average AAA rotation could pitch significantly better (though Coors Field wouldn’t make it easy). Jamie Moyer’s -60 is only three points better than Jair Jurrjens’s NL-worst -63.
The worst rotation in the American League has been the Twins, who are led by Scott Diamond’s 30 TSS. Among the pitchers in their opening day rotation, Carl Pavano’s -31 is best. Adjust for park effects and the DH, as WAR does, and the Twins’ starting pitching has been worse than the Rockies’.
I don’t expect much to change if we look at these ranking again a few months from now. The Nationals may fade some, as Gonzalez and Detwiler are exceeding expectations, but they’re a legitimately good rotation. The Rays may move up and the Rangers may climb into the top ten. At the bottom, what you see is what you get, as the Rockies and Twins have horrible rotations.