The Diamondbacks Rotation: There Will be (NL-Only) Value

It’s time for our Depth Chart Discussions to begin. In an effort to suss out every team, we’ve divided them into four parts (infield, outfield, bullpen, and rotation) and will begin breaking them down for you over the next few weeks. You can find them gathered here.

The 2014 Arizona Diamondbacks rotation was….not good. As a staff they had the fifth lowest WAR total in the league and the fourth worst ERA. The staff’s xFIP was three quarters of a run lower than their ERA meaning they were slightly above average in that respect. But the main reason for that was the enormous ERA-xFIP gaps for Brandon McCarthy and Wade Miley, both of whom will play for different teams this year. There are still a couple of guys on the staff who may be in line for some positive regression, and there’s a whiff of upside from a couple of guys. But not one of the five starters projected by Steamer to pitch the most innings for Arizona has a FIP projection of 4.00 or lower.

There are only two Arizona starters projected to top 150 innings, Josh Collmenter and Jeremy Hellickson.

Collmenter was easily the team’s most fantasy relevant starter last year as he rode a 3.46 ERA and 1.13 WHIP to being a borderline top 50 fantasy starter. I actually wrote up the Arizona bullpen last year when we did depth chart discussions, and I praised Collmenter’s 2013 season as he performed much better against left-handed hitters and generated more swings and misses. As a result, I said he could post an ERA in the mid-to-high threes and be a relevant fantasy spot starter if he got work in the rotation.

As right as that discussion of Collmenter turned out to be, it had absolutely no business happening as Collmenter wasn’t as good in the rotation as he was in the bullpen. Shocking, I know. The things Collmenter did well that impressed me in 2013 did not happen again last year. Lefties posted a .289 wOBA against Collmenter in 2013 and a .327 wOBA against him last year. His K-BB% against lefties fell from 13.2% to 8%. And that new found ability to generate swings and misses? He lost it when he moved to the rotation. His swinging strike rate fell from 10.8% in 2013 to 7.7% last year.

Collmenter managed to post the mid-three ERA despite a 4.18 SIERA primarily because of his fly ball tendencies. He had the 16th highest fly ball rate among 87 qualified starters last year, which helped him post a .267 BABIP (.271 career). Being a fly ball pitcher can be dangerous, but Collmenter has a pretty good track record of keeping the ball in the park with a career 8.4% HR/FB rate. League average for starters last year was 9.8%.

Because Collmenter has a little over 500 career innings with a below average BABIP and HR/FB rate, it would be dismissive to assume he can’t continue to do so. Which is why Collmeneter having an ADP of 104 among starters is a little pessimistic. That said, it would seem that last year was the best case scenario for him as a starter, so there’s no reason to draft him in shallow mixed leagues when he was borderline ownable in those formats last year. But in deeper mixed leagues and NL-only leagues, his draft day price likely won’t represent anything close to what he was worth last year, which makes him someone to target late in those formats. And in the shallower mixed leagues, keep his name in mind for spot starts when he’s starting on the road in some of those favorable NL West ballparks.

As for Hellickson, he’s going even later than Collmenter. And rightly so given that he only threw 63.2 bad innings last year. Whatever strand rate mojo Hellickson had going on from 2010 to 2012, it’s gone now. And unless it comes back, it’s hard to imagine Hellickson being useful. Hellickson is a fly ball pitcher like Collmenter, but Hellickson does not have an established track record of keeping the ball in the park. His career HR/FB rate is 10.2%, and his career HR/9 is 1.17.It’s hard to imagine those numbers getting any better as he moves from Tampa (95 HR park factor) to Arizona (104 HR park factor).

Pod rightly points out that Hellickson has good stuff and strikeout upside, which maybe makes him worth a shot in NL-only leagues. Especially since you could probably get him after pick 200 in that format. But that’s the extent of his fantasy relevance.

Now, about those guys who had an xFIP below their ERA last year that are still Diamondbacks. That distinction belongs to Chase Anderson and Trevor Cahill. Let me quickly dismiss Cahill because Anderson is more interesting.

As a starter, Cahill’s ERA was 6.31, but his xFIP was an even 4.00. His BABIP and strand rate were cartoonish at .352 and 59.2%, respectively. Surprisingly, his strand rate issues had little to do with home run issues, an issue Cahill has always had. A big part of the problem was a woeful walk rate of 11%, which is another problem Cahill has always had, but last year it got even worse. The point is that he’s definitely in line for some positive regression, but it really doesn’t matter to us given his serious issues with home runs and walks. No thanks.

As for Anderson, there’s a lot more to like. The problem is that I’m not sure how much of a chance we’ll be given to like it. Steamer is projecting Anderson for 13 starts, while he’s currently listed seventh on Arizona’s website depth chart. The Fan projections have him making 23 starts, and I’m having a hard time understanding why he wouldn’t make at least that many starts. Hellickson and Cahill are both ahead of Anderson on the depth chart, and, as I’ve just detailed, they’re not very good.

But Chase Anderson is kind of good. As I noted back in August, his changeup is damn good. Of the 85 starters who threw 200+ changeups last year, Anderson’s change had the 14th best whiff rate (per the BP PITCHf/x leaderboards). As Eno noted this offseason, he’s also got an above average curveball and a fastball/sinker that are at least close to average. To give you an idea of how good the curve is, Anderson ranked 19th in whiff rate among 105 starters who threw at least 200 curves last year.

Someone is going to have to explain to me why it’s even a possibility that a guy with two plus secondary pitches who was entirely decent in his first 21 major league starts might cede rotation work to the likes of Cahill and Hellickson. Not to mention that there are two other starters we have projected to throw more innings than Anderson that we have yet to discuss. If Anderson ends up with a rotation spot, as he should, he will provide value in fantasy leagues. He’s going completely undrafted in mixed leagues and borderline undrafted in NL-only leagues with a mixed league ADP of 452 overall. That ADP will move upward if he wins a job in Spring Training, but it probably won’t move up as much as it should. Keep your eye on the Arizona rotation in the spring, and keep Anderson in mind.

As mentioned, there are two other guys projected to throw more innings than Anderson, Rubby de la Rosa and Allen Webster. Both are completely off the radar as they’re being drafted even later than Anderson. But if they really do have a rotation spot, does either one of them represent a potential value in NL-only leagues?

As for Webster, there’s no doubt that he could potentially return plenty of value on a late round NL-only pick. Eno has noted his surpisingly good arsenal, and Pod has noted his strikeout upside. His control issues are a big problem, but a guy going that late has to have some warts. Pod also noted de la Rosa’s strikeout upside in that same post, but he doesn’t have the secondary stuff that Webster does. Of the two, I’d rather take a flier on Webster, especially given de la Rosa’s injury history, but one or both could easily end up being worth a flier.

So far I’ve mentioned six names here and have yet to mention Vidal Nuno (who is listed fifth on Arizona’s depth chart), Daniel Hudson who is listed eighth on the depth chart, and Bronson Arroyo and Patrick Corbin who will return from injuries at some point this year. Nuno had average-ish strikeout and walk rates last year with a 3.99 SIERA. Hudson was pretty useful prior to a couple of Tommy John surgeries that have essentially cost him two seasons. Arroyo isn’t all that interesting, but Corbin’s first full season in 2013 was more than promising, so expect waiver wire columns to be pimping him once we get closer to summer and his return date. Hell, we’re almost 1,500 words in and haven’t mentioned Archie Bradley, Arizona’s top pitching prospect who should be in the big leagues at some point this year.

Ultimately, there are way too many names here to know exactly how this rotation is going to shape up. That’s if it even shapes up. There’s a good chance it’s constantly in flux this year. But there are useful pieces. Collmenter can help an NL-only team and is potentially a mixed league spot starter. Anderson is definitely a great NL-only pick if he has a rotation spot and is possibly mixed-league worthy. Webster and de la Rosa have upside. Nuno is potentially unexciting but useful in NL-only leagues. Bradley is interesting as all prospects are. Corbin and Hudson have had mixed league success in the past and will be very interesting if they make it back to the rotation.

I don’t know for sure where the useful pieces and value will come from exactly. But I am sure that at least a guy or two from this staff will help fantasy teams this year, especially in NL-only leagues. Just don’t ask me to tell you exactly which guy or two that will be.

We hoped you liked reading The Diamondbacks Rotation: There Will be (NL-Only) Value by Brett Talley!

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Does anyone else hate the term “positive regression” to talk about performance improvement? That’s a contradiction in terms used that way.


You’ve never heard of “regression to the mean” or “regression analysis?” For both of those terms, a negative value is not assumed.


Sure I have; I understand the meaning of regression in statistical analysis. But in this context it is not statistical analysis. All that was implied is likely improvement/progress, particularly of young players with little major league history on which to base movement to or from a mean.


No its not, because it refers to regression to the mean which can be positive or negative. Regression does not in and of itself mean negative when talked about in statistics.