The Diamondbacks rotation in 2015 and beyond

There are certainly no shortage of options. Right now, I can think of no less than fifteen potential starting pitchers for the Diamondbacks in 2015. Ten pitched in the majors last season (all but Hellickson for the Diamondbacks), two are coming back from Tommy John surgery, and there are three prospects whom MLB.com reckons should arrive in the majors. Of course, not all will be ready for Opening Day, and some might end up not being ready at all. On the other hand, comments suggest the team is still looking to add even more, with Chad Billingsley still reported to be on the Diamondbacks' radar.

Now, it has been said before, and it certainly should be stressed, that you are going to need more than 5 starters in a season. Last year, the most "reliable five" for the Diamondbacks started 117 games, with the remaining 45 being covered by a committee of six other pitchers. Depth is a good thing, because it means you can replace a starter that goes down, with one that has a chance of being as productive, thereby lessening the impact of the injury. But, on the other hand, you don't get any more MLB wins, just for having a kick-ass rotation waiting in Triple-A. If someone isn't on the 25-man roster, they're not contributing.

But for now, here's a chart, summarizing the possible candidates going forward for each season, along with their cost. [* = team option for that year, ^ = mutual option]. The service time clock presumes full years for everyone, so is almost certainly pessimistic, i.e. we may well end up controlling Bradley past 2020.

Let's take a quick look at each of these, and see what the situation is.

Trevor Cahill. The ultimate reclamation project, the team is already on the hook for an eight-figure sum, so I guess they might as well see whether Cahill can figure out what ails him. Because I'm pretty sure nobody is going to want to take much of his contract off our hands.

Bronson Arroyo. Should be back sometime in 2015, but it'd be a braver man than I who would bet on when, how he'll perform, or whether it will be good enough for Arizona to pick up the 2016 option. Even if they don't, Arroyo still gets paid $4.5 million for that, so his "real" cost for 2016 is $6.5 million. Will that be economical enough for the team to bite?

Josh Collmenter. Is the team really thinking of moving our best starter last year back to the bullpen? I would be hard pushed to find that a sensible move in terms of getting the most out of him. It's very obvious: Collmenter's value has been directly tied to the number of starts he makes

• 2011: 24 starts, 1.9 bWAR
• 2012: 11 starts, 1.3 bWAR
• 2013: 0 starts, 0.9 bWAR
• 2014: 28 starts, 2.4 bWAR

Daniel Hudson. The original plan was for him to work out of the bullpen, but the team seems to be aligning around trying for a return to the rotation. "We'd like to best utilize him in a way that we can get the most out of him," said Stewart.  However, don't expect 200 innings, even if all goes well: beginning in relief, then transitioning to the rotation seems much more likely.

Jeremy Hellickson. According to Stewart, Hellickson will move into the #2 or #3 spot in the rotation - but I think this says more about how thin we are at the top [I'm also wondering who he thinks is the #1?] He's probably the closest thing to a lock for the rotation, especially being the new GM's shiny first acquisition.

Wade Miley. The other "sure thing" as far as the 2015 rotation is concerned, but I'm not necessarily sure how much longer beyond that. He's entering arbitration, so will probably earn close to $4 million next year, and the 86 ERA+ posted last season won't cut it for much further beyond that. Hopefully, he'll rebound to at least 2013 levels, or better yet, 2012 Rookie of the Year runner-up form.

Patrick Corbin. Highly unlikely he'll be back by Opening Day, with June a more likely estimate. He was very solid as a 23-year-old in 2013 (ERA+ 113), but will he be the same pitcher after Tommy John surgery? I wouldn't expect much out of him next year, but at least he's still in his pre-arbitration years.

Randall Delgado. Did get a couple of starts in September, suggesting new management might want to see what he can do in the role, and he did finish the year strong, posting a 1.53 ERA that month, with a K:BB ratio of 16:3 over 17.2 innings. More of that in spring, and he could find himself back in the conversation again.

Vidal Nuño. Will the Diamondbacks ever Win Uno for Nuño? The world's unluckiest pitcher, who came up short in his first 14 appearances for ARizona, might now find himself on the outside of the rotation looking in, at least on Opening Day, as the available spots appear to be shrinking.

Chase Anderson. Right now, I would think it's probably down to one of Delgado, Nuño and Anderson for the fifth spot on Opening Day. But even assuming there are no more additions, that's probably just just a place holder until Corbin or Arroyo return, whichever comes back first.

Mike Bolsinger. Made nine starts in the first half of the season, then apparently vanished off the face of the mound, and wasn't seen again after the break. Probably because those starts weren't actually very good. I'm getting an Andrew Good vibe here. If you response is to ask "Who?", that's probably about right.

Andrew Chafin. He perhaps represents the bridge between the "past" and the "future" candidates, having made precisely one appearance in the major-leagues, as part of a double-header. It went well - five shutout innings - and one suspects there will be more in future.

Archie Bradley. Our top prospect is beginning to feel like the titular character in a certain Samuel Beckett play. We've been sitting around, for what seems like forever, talking about Bradley, and waiting for his arrival. But we'd do well to remember, he only turned 22 in August. No point starting that service clock unless it'll make a difference.

Braden Shipley. Seeing him this year might be a bit of a stretch, considering he has only thrown twenty innings above High-A ball to this point. But we have seen pitchers be promoted from Double-A to the majors and have some success - that's what Anderson did this year. If the talent deserves it, there's something to be said for letting them learn in the majors, the counterpoint to the service clock argument mentioned above.

Aaron Blair. A really strong second half, with a 1.94 ERA after his promotion to Double-A Mobile, has certainly boosted Blair's stock, and made him one to watch for the future. As with Shipley, I'm more inclined to think 2016, especially given the sheer number ahead of him.

Putting it all together, here's where I think the 15 listed above will end up on Opening Day 2015:

• Rotation: Miley, Hellickson, Collmenter, Cahill, Nuño
• Bullpen: Delgado, Hudson
• Disabled list: Arroyo, Corbin
• Triple-A: Anderson, Bolsinger, Chafin, Bradley
  
• Double-A: Blair, Shipley

There may be other pitchers who show up over the course of the coming years, but there isn't anyone else in our top twenty prospects currently projected to arrive much before 2018, when the likes of Touki Toussaint should be well on the radar. Probably best if we get through the next couple of seasons before worrying too much about that!