Los Angeles' rotation is built around a true ace, Clayton Kershaw, that they drafted and developed. Around him is a testament to new ownerships resolution to become 'Yankees East': Zack Greinke, Josh Beckett, Hyun-Jin Ryu and Aaron Harang.
Washington took an inverse strategy, poaching only their fifth starter, Dan Haren, off the open market. The front of the rotation is the product of their deep minor league system; Stephen Strasburg, Ross Detwiler and Jordan Zimmermann were first-round picks and Gio Gonzalez was netted by trading prospects.
The debate that ultimately doesn't matter, but is interesting nonetheless, is which rotation is the best?
In reality, the pitching staffs in front of us today are different than what we'll see on Opening Day. The Dodgers will probably trade some of their surplus and Washington should add some depth. However, we'll do the best with what we have now. Speaking of which, the approach I want to take is limited by what we have now; in that, I'd like to look at what projection systems think of these pitchers rather than their past performance. The constraint here is that some of the best projection systems out there, PECOTA, Oliver, ZiPS aren't yet available. Luckily for us, Bill James projections are available on Fangraphs and will do the trick*.
*Except for ground ball rates, those aren't projected, so we'll settle for career rates.
To attack this, we'll take it pitcher by pitcher, in a sort of head-to-head matchup. Starting with our respective 'Aces'.
Clayton Kershaw vs. Stephen Strasburg
Kershaw's projected line: 2.65 ERA, 9.24 K/9, 2.44 BB/9 and 43.4 GB%
Strasburg's projected line: 2.68 ERA, 11.03 K/9, 2.71 BB/9 and 44.5 GB%
Arguably the two best pitchers in the National League, this really is a toss-up. With a gun to my head, I'd take Kershaw because of his track record and durability thus far.
Zack Greinke vs. Gio Gonzalez
Greinke's projected line: 3.46 ERA, 8.47 K/9, 2.31 BB/9 and 41.9 GB%
Gonzalez' projected line: 3.21 ERA, 9.09 K/9, 3.70 BB/9 and 47.7 GB%
Both would be #1 starters on most teams, but have to take a back seat in these rotations. Greinke and Gonzalez put up great peripheral numbers, but with different results; Greinke has consistently underperformed his skills while Gonzalez has outperformed them. Given that fact, I'll take Gio until Greinke proves me wrong.
Josh Beckett vs. Jordan Zimmermann
Beckett's projected line: 3.26 ERA, 7.91 K/9, 2.64 BB/9 and 44 GB%
Zimmermann's projected line: 3.32 ERA, 7.44 K/9, 1.94 BB/9 42.4 GB%
The fact that Beckett and Zimmermann are on very different stages in their career isn't reflected by these projections. Beckett has lost velocity and struggled in 2012 leading to questions about whether he's on the decline; he may not be completely finished he's certainly no longer the ace Boston traded for. Zimmermann, on the other hand, is becoming an elite starter in the National League.
Hyun-Jin Ryu vs. Ross Detwiler
Ryu's projected line: ???
Detwiler's projected line: 3.98 ERA, 6.10 K/9, 3.00 BB/9 and 46.8 GB%
We know nothing about Ryu, he could be great or a bust or somewhere in between. Somewhere in between is probably what the Dodger's will get. On the other hand, the Nationals' already know they have an above average guy in Detwiler. Ryu is intriguing and certainly has potential, but Detwiler's the obvious choice as of now.
Aaron Harang vs. Dan Haren
Harang's projected line: 4.53 ERA, 7.18 K/9, 3.80 BB/9 and 38.2 GB%
Haren's projected line: 3.47 ERA, 7.68 K/9, 1.69 BB/9 and 43.2 GB %
Like Beckett, I'm not sure how much to trust Haren's gaudy projection; he's past his prime and lost velocity last season. He could bounce back in the National League with less pressure, but I wouldn't bet on him returning to his frontline starter past. Harang on the other hand is pretty predictable, he'll be average and eat innings. I'll usually take the sure thing, but in this case, it's hard not to take what's left of Haren's upside.
With the Nationals winning 4 out of the 5 head to head match-ups, the choice looks pretty close. However, it's a lot closer than at first blush. The Dodgers back up their five with Chad Billingsley (once healthy), Chris Capuano, Ted Lilly and minor leaguers John Ely and Stephen Fife. In contrast, if any of the Nationals starters fall their replacement is Yunesky Maya. That contrast in depth will make a huge difference in 2013, just not enough to push the Dodgers above the Nat's.
Winner: Washington Nationals