Leave it to the Arizona Diamondbacks to make a transaction that ought to have you scratching your head in bewilderment.

About said transaction, this happened on Friday: The Diamondbacks agreed to terms with veteran right-hander Bronson Arroyo. Ken Rosenthal of FoxSports.com had the news first:

According to ESPN’s Buster Olney, Arroyo will make $9.5 million in 2014 and 2015 and has a $4.5 million buyout on an $11 million option for 2016. So he’ll make at least $23.5 million in two years, and potentially $30 million over three.

Because you read that first paragraph up there, you know I have some not-so-nice things to say about this deal. Before we get to those, I want to say some nice things first. It’s not like this is the worst deal ever made, after all. Another Barry Zito didn’t just happen.

For one, the money is fine by this market’s standards. Arroyo’s deal is essentially a modified version of Tim Hudson’s two-year, $23 million deal with the San Francisco Giants. And as I wrote last week, the $30 million Arroyo could earn over three years is perfectly fair given both his age and his track record.

Shoot, the guy’s a solid pitcher. He’s good for over 200 innings like clockwork. And while his peripherals are sketchy, you have to hand it to the guy for consistently posting ERAs in the 3.00s despite pitching at Great American Ball Park half the time.

So no, my issues aren’t with Arroyo’s contract or Arroyo himself. It’s how he fits with the Diamondbacks that bugs me.

Before the Diamondbacks signed Arroyo, their projected starting rotation looked like this:

  1. Patrick Corbin
  2. Trevor Cahill
  3. Wade Miley
  4. Brandon McCarthy
  5. Randall Delgado

Maybe they wouldn’t have ended up in that exact same order, but it was going to be those five guys. Not a bad rotation, at that.

But not a great rotation either. The Diamondbacks seemed to realize that, as ESPN’s Jerry Crasnick reported in December that Arizona wanted to add a “top-of-the-rotation starter.” You know, somebody like David Price or Jeff Samardzija off the trade market, or Masahiro Tanaka off the open market.

Adding one of these guys would have made sense. The top of Arizona’s rotation would have gotten a boost, and the ripple effect most likely would have been Delgado being booted from the mix. He was the weak link in Arizona’s rotation last year, after all, finishing with a 0.2 fWAR.

Well, the Diamondbacks didn’t get one of those guys. They got Arroyo. Now that he’s in, Delgado is very likely still the odd man out. While that may look like a good swap considering Arroyo’s track record, here’s the thing:

If you look at certain numbers, he and Delgado are basically the same pitcher.

Via FanGraphs, here are the “certain numbers” worth looking at, all of which are strictly from 2013:

Delgado was better at striking guys out. Arroyo was better at not walking guys and getting ground balls. But the differences in those three categories are very slight, and that speaks to the reality that both pitchers are certainly more crafty than overpowering.

And as far as xFIP—a version of FIP that tries to normalize a pitcher’s home run rate—is concerned, Delgado’s crafty style was every bit as effective as Arroyo’s crafty style. That xFIP column, which shows xFIP figures scaled to league average, says the same thing. SIERA, or “Skill-Interactive ERA,” is yet another sabermetric thingamajig that says the two pitchers were basically clones in 2013.

Delgado will only be 24 in 2014. He’s under club control through 2018. He’s not going anywhere, and he’s going to be cheap for a while. Yet this didn’t stop the Diamondbacks from agreeing to pay $23.5 million for Arroyo to basically be an older, more expensive Randall for a couple of years.

Now, OK, sure. You can argue that the expense is justified by the fact that Arroyo is a proven innings-eater, something Delgado is not. The Diamondbacks are very likely to get a couple 200-inning seasons out of Arroyo, which is not a bad thing.

But let’s give Delgado some due credit. He pitched 114.1 innings in 19 starts in 2013, an average of six innings per start. Before Arizona signed Arroyo, the Steamer projections had Delgado down for 182 innings in 32 starts. A bit conservative, perhaps, but fair enough.

So in all likelihood, the Diamondbacks aren’t paying $9.5 million a season for Arroyo to rack up dozens more innings than Delgado. Since he hasn’t pitched any more than 202 innings in any of the last three seasons, he’s likely to only give them maybe 20 more innings than Delgado might have given them.

That’s not that many extra innings for so many extra dollars. The Diamondbacks have upgraded, but it’s not nearly the kind of upgrade they had in mind when they conjured plans to go acquire a top-of-the-rotation starter.

The good news for Delgado is that he’ll still be needed, of course. It stands to reason that he’s now the first in line to step into the rotation in the event of an injury. And when you have Brandon McCarthy on your staff, it’s a good idea to have a guy like that.

But with Delgado lower on the rotation ladder, another guy who’s now lower is Archie Bradley. That might not be the best thing for the Diamondbacks.

Bradley is the top pitcher in MLB.com’s prospect rankings, and he looks darn near ready for the show after posting a 1.97 ERA in 21 starts at the Double-A level in 2013. In fact, Nick Piecoro of AZCentral.com wrote just this week that Bradley doesn’t hesitate to say he’s ready for the majors. And with spring training coming up, he was hoping to put his foot in the door.

“My goal isn’t to win the fifth spot,” said Bradley, “it’s to make them, every day when they go into meetings, have to think, ‘Hey, he’s doing everything he can. He’s putting pressure on us.'”

Who knows? Maybe Bradley could have won the No. 5 spot in Arizona’s rotation this spring by dominating while Delgado or one of the veterans struggled. Either that, or he could have stepped in early on in the season after an injury or a demotion. In effect, he had a shot to be what Gerrit Cole was for the Pittsburgh Pirates in 2013.

With Arroyo coming aboard, though, the possibility of Bradley being the next Cole just got a little more unlikely. Given Bradley’s absurd talent, it’s possible that the Diamondbacks will now miss out on a handful of dominant starts in 2014. Maybe even more than a handful.

One can think of worse ripple effects than that, to be sure, but that the Diamondbacks were comfortable with allowing it to happen is puzzling. Bradley’s a guy they should want on a fast track to the majors, and they just buried him a little deeper. That they did so for the sake of paying big bucks for a piece of equipment they already had only makes it more puzzling.

But then, these are the Diamondbacks. They couldn’t wait to get rid of Justin Upton. They couldn’t wait to get their hands on Mark Trumbo. Lest we forget, they also dealt a solid third base prospect for a relief pitcher.

You never know what they’ll do next. All we know is that Diamondbacks gonna Diamondbacks.


Note: Stats courtesy of Baseball-Reference.com unless otherwise noted/linked.


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