Last month I noted how pitchers usually don't recover after a CC-like decline from top-of-rotation starter to 80ish ERA+, but the outcomes varied widely: about a third of the comps did recover, half stayed lousy, and a fifth recovered underwhelmingly minimally. Given that range of variation, I wanted to look for comps a different way. Staring at CC Sabathia's stats since 2013, you see not just a gradual ERA worsening, but a real consistency in his HR, BB, and K rates – the defense-independent pitching components that may be more telling of true talent level than ERA, the noisy bottom-line stat. 2013: 1.2 HR/9; 2.8 BB/9; 7.5 K/9; 4.78 ERA 2014: 2.0 HR/9; 2.0 BB/9; 9.4 K/9; 5.28 ERA 2015: 1.6 HR/9; 2.0 BB/9; 7.6 K/9; 5.45 ERA
The ERA decline jumps out at you, but you're actually seeing a guy who's evolved into a pretty consistent profile: high-control, high-strikeout, high-homer. While the K and BB rates are strong, the big question is: can you remain a major-league starter giving up more than a home run every 5.2 IP? I was skeptical.
So I looked up a new set of "CC comps": starters in the past five years with high HR rates (1.4-2 HR/9), high K rates (6.5-10 K/9), and low BB rates (1-2.99 BB/9). It's an interesting list - and not as hopeless as I thought I'd find.
To my surprise, it's not that uncommon to remain a useful starter while giving up 1.4-1.6 HR/9 – the range of most of the above pitchers. The group averaged 0.8 WAR, which is fine for a fifth starter. So I now think CC deserves his rotation spot at least as much as Adam Warren or Chase Whitley – who are younger, but at 27 and 26, they're not so young that you really can expect them to improve beyond what they are: roughly replacement-level fifth or sixth starters.
But let's not overstate what these comps show: 1-WAR fifth starter is not only CC's likely level, but also his likely ceiling. Look at the FIPs: even the best of the comps were stuck with a FIP from 4.1 to 4.8 -- and mostly 4.4-4.7. Those with an ERA in the 3s or low 4s, and WARs of 2-4, seem to have been lucky to beat their FIPs substantially. You really can't give up that many HR and expect an ERA below the mid-high 4s, or a WAR much above 1, unless you get lucky and have your 30something HR come disproportionately with the bases empty. Even CC's notionally good starts - like last night's 3 ER in 7 IP - come with a dose of luck, in that when a starter gives up 2 HR, he rarely gets away with just 3 ER; you can't count on regularly lucking out with (A) that few runners on base for your HR, and (B) getting away with no other runs than on the HRs. That might happen, but it's just as likely a 2-HR start becomes a 5- or 6-ER start.
The pre-season hope was that with his degenerative knee successfully managed, CC might return to being be a solidly average starter - a #3 starter in casual terms, or more specifically a 2-3 WAR pitcher - and that's clearly looking like it's not in the cards. But I think we'll all be happy, or at least grudgingly satisfied, with CC gritting out the roughly 1-WAR season that these comps indicate might be realistic. The team could do a lot worse than a fifth starter who can give you a full season of 6.5 innings per start at a 4.50 FIP -- CC's 2015 averages so far.