MLB Opening Day 2016: Who'll be the Arizona Diamondbacks last reliever?

"We're kind of weighing and debating back and forth in the room what's our best roster. That one spot has really been a great battle. You talk about the middle infield -- that last reliever spot might be a better battle than that."
-- Chip Hale

We already discussed the fraught process of trying to evaluate bullpen pitchers on the basis of spring training performances, but a quick recap is in order (a.k.a. "previously, on AZ SnakePit..."):

• Reliever volatility - anyone can have a bad week or two.
• Severely limited sample-size, just a handful of innings.
• Huge variations in the quality of batters faced.

As said there, "It's safe to say assessment is going to be much more based on how the coaches and Chip Hale sees them looking in bullpen sessions, on back fields, etc." and we just do not have access to that data, which makes it very hard to figure out how Hale ranks the contenders. However, at least it seems we're still looking at the same situation: no health issues of significance have surfaced that we know of, and six spots are locked up. Brad Ziegler as closer, Daniel Hudson and Tyler Clippard as set-up men, with converted starters Josh Collmenter, Randall Delgado and Andrew Chafin occupying long-relief, mid-inning + left-handed roles.

Every indication seems to be that we'll be sticking with the traditional seven-man bullpen (or, at least, there have been no signs of any other approach), which means just the one open slot. Who gets that will depends on, among other things, whether or not they are happy going with one left-hander (Chafin), or if they want someone to occupy a more traditional LOOGY role. That decision appears to come down purely to performance, with the team inclined to take the best pitcher, regardless of side. Said Hale, "These guys have to show us that they're more important than a last righty that's a power guy."

That all said, here are the stats for the slate of reliever in camp. I've separated the list into three categories. First, the six players listed previously, who appear to have their spots assured. Then, the group of most likely contenders for the seventh slot. And, mostly for amusement, players who seem unlikely to make it for Opening Day, but who have put up some impressive numbers, one way or another - collectively, they've throw fifteen scoreless innings and allowed a mere five hits, with a K:BB ratio of 19:6.

The certs

Bit of a mixed-bag in the performances here. Delgado and Hudson have looked good, putting up ERAs little north of two, with both men also having excellent K:BB ratios. Behind them, however, we see some struggles, though the causes vary. Clippard has had issues with location walking almost as many as he has fanned, while for Josh Collmenter,. the problem has been the balls which haven't come back. Chafin has seen limited action in games, with just 1.1 innings since March 9, but has seen backfield action, throwing two innings in a minor-league game on the 22nd, for example. Ziegler has had bad luck, with a BABIP of .455, so should be fine.

The possibles

So, who've you got? You could make a credible case for just about any of them. If there's going to be a left-hander chose, Wesley Wright seems to have a clear edge so far. Not just because of his solid numbers, but because his main rival, Matt Reynolds, was removed from the game on St. Patrick's Day with an apparent rib/oblique injury and hasn't pitched since. At least it wasn't an apparent arm issue for the Tommy John alumni,, but with time running out as we move toward Opening Day, every game in which Reynolds does not pitch, tightens the noose of roster re-assignment further around Matt's neck.

Among the right-handers, Jake Barrett has posted video-game numbers, striking out 13 in 8.1 innings of work - more than Shelby Miller or Zack Greinke this spring - though you'd have to dig into the game logs to find out if these were major-league hitters, or if he was chewing up roster filler in late innings. Enrique Burgos and Silvino Bracho have been engaged in their own personal battle, much as they did late last season, while Evan Marshall is a good demo of the volatility mentioned. He looked great in his first six appearances, then got taken to the woodshed late in yesterday's contest, and his spring line now looks much more pedestrian, right alongside that of Sam LeCure.

Conclusion

I can't say I would be particularly upset with any of the possibilities; it's not like any of them have resembled Heath Bell, and the last man in the bullpen is not likely to see many high-leverage situations. That this is the biggest question regarding our bullpen, with a week until Opening Day, is not a bad thing. Emotionally, I'd like to see Marshall make it, just to complete his comeback. But I suspect the team may go with Wright if they want an extra left-hander, or Silvino Bracho if they prefer to go with a power right-hander, as Hale mentioned. But that's what the poll and the comments section are for...