With the arrival of Kelly Johnson, and as we sit on the very last day of the year, with 2010 virtually upon us, the mist surrounding the shape of the Diamondbacks next year is beginning to clear. While there are still a number of question-marks, things are significantly closer to being resolved then they were during the post-season - or even at the start of this week. With that in mind, after the jump, we'll take our opening shot at putting together the 25 men we might see in Arizona on Opening Day. We'll be dividing them into three categories: definites, probables and possibles.

Let's start off with the players who, at the time of writing, appear to be solid locks for the roster. If any of them were not present on  Opening Day, I think this would be a big surprise. There's not been much word of the team seeking to strengthen these spots, and so we will put their names on the roster in bold.

Most of the above should be fairly self-explanatory. The only questions might be over the roles of some of those named. For example, Roberts might be on the bench or he might be the starting left-fielder, if Jackson plays first - but, either way, he seems certain to be on the roster. The same goes for relievers Heilman and Howry. They may or may not be the actual set-up men, pitching the seventh and eighth innings - that will likely depend on performance - but their position on the team is assured. They certainly bring experience: after Qualls went down last season, during the final month, Scott Schoeneweis was the only one of the relievers used by Arizona, who was older than 28.

Now, we'll move onto those who, while not certain, are probably more likely than not to be present. Their situation or role could still fluctuate as a ripple effect from changes elsewhere on the team, but in the absence of anything like that, their positions will likely be as listed. Even if not, they should still be part of the 25-man roster. We'll take the above chart and add their names to the roster in plain text. I'll go into more discussion about each case after the table.

As the cash in the coffers heads towards zero, it seems the team is content to go into 2010 with Brandon Allen as the starting first baseman. There will likely be an element of platooning, with Jackson at first against left-handed pitchers. In the outfield, Chris Young finished the season solidly, after his return from Triple-A, and is likely to get a chance to redeem his wretched 2009. The same is true for Eric Byrnes: while I'm sure the team would love to deal his contract away, it's hard to see anyone biting, and he'll likely be our fourth outfielder, getting starts in LF when Jackson plays first. Gerardo Parra should be the fifth, seeing action mostly when we face left-handed pitchers.

Speaking of which, that's a spot which is shaping up as potentially a issue in the 'pen. Zavada is currently the only southpaw to pitch for the 2009 Diamondbacks who'll be on the 2010 roster: Daniel Schlereth, Doug Slaten and Scott Schoeneweis are all basically gone.The selection of Zach Kroenke from the Yankees in the Rule 5 draft makes some sense in the light. As a Rule 5 pick, Kroenke has to be kept on the roster all year or offer him back to the Yankees for $25K. [Additionally, Nick P says, "as a player selected twice in the Rule 5, he can elect free agency if taken off the roster."]

Now, that doesn't guarantee him a roster spot - just ask catcher James Skelton, our rule 5 pick last year, who had a dismal spring and ended 2009 down in Visalia. But given Zavada showed reverse splits last year [better against RHB than LHB], one suspects the team will be hoping to use Kroenke against left-handed batters out of the 'pen. Last year, he held them to a .196 average in the minors, and throughout his career there, has also been more of a ground-ball pitcher against lefties [57.4% vs. 47.7%]. This would allow Zavada to remain as a more general relief arm, working against hitters on both sides of the plate. But what if Kroenke crashes a la Skelton? What's Plan B?

I put Boyer in the long relief spot, as ten of his thirty appearances for Arizona last year lasted 1.2 innings or more. He performed very nicely for us in 2009, though the ERA projections to date for Boyer in 2010 are not exactly awesome (Bill James: 4.74, CHONE: 4.67). Still, got to like his overall groundball-flyball ratio of 1.72 this season [league average is 0.80!] in 54.2 innings, and if he can continue in that vein, I think he'll perform significantly better than expected. Finally, Billy Buckner, in the absence of any other changes, has the best shot at the fifth spot, courtesy of the solid September starts after he added the cut fastball to his repertoire.

This only leaves two spots to be decided: one at the back of the bullpen, and the other would be a position-player spot, unless we decide to go with an extra bullpen arm, as we did for some time in 2009. Otherwise, it will most probably an infield backup. In the bullpen, there are a number of potential candidates, but an additional factor we need to take into account is what happens to the other players if they don't make the roster. The three main candidates all pitched significantly for the Diamondbacks last season: Gutierrez (71 IP, 4.06 ERA); Vasquez (53 IP, 4.42 ERA) and Rosales (45.1 IP, 4.76 ERA).

On performance, it's an easy choice, especially if you look at FIP: there, Gutierrez was the best on the team, at 3.00, with Rosales (3.96) and Vasquez (4.19) some way behind. This is fortunate, since Gutierrez is also out of options. On that basis, if it were my decision, I'd stick him in the final pitching spot. Vasquez can be optioned to Reno, which leaves Rosales as the odd man out. The Diamondbacks could, I suppose, retain Rosales, optioning Zavada to Reno instead - their FIP last season was very similar (3.92 for Zavada). Hmmm. Upon further consideration, I think I'll put Gutierrez on roster v3.0 as a lock, and move Zavada to the "on the bubble" section.

That leaves the 25th spot, which really comes down, at the moment, to Ojeda and Abreu. This should be decided in a steel-cage death-match between the two, as part of the March WWE pay-per-view. Hey, I'd watch. The issue may be resolved less violently, if the team can trade Ojeda between now and Opening Day. I am inclined to think this is the most likely scenario, but this exercise has excluded all future potential moves, and I see no reason to change that here. So we'll assume - for the moment - that both players remain on the roster and a decision has to be made.

Abreu is generally projected to have better offensive numbers in 2010 than Ojeda, and that seems almost certain to come true. However, as the 25th player, it hopefully won't make much difference, due to a lack of playing time. Our previous #25, Ryan Roberts saw only 29 PAs in the first quarter of the season, while 2008's last man standing, Robbie Hammock, got even less: 24 PAs over the same time-frame. [This inactivity may also be an argument in favor of going with eight bullpen arms] Such limited action would hurt a developing player like Abreu a good deal more than Ojeda, and he may be better served by getting regular time in Triple-A - which would also stop his service-time clock.

Given this, I'd be more inclined to have Augie around; we can make full use of his mad defensive skillz as a late-inning replacement for Johnson or Drew, and this way, his limited offense will be less of a factor. However, much as I love Augie, if we get a good offer for him - and given the roster is almost full, I'd be thinking more prospect than MLB-ready plater - then it's something I would do. So, with the last couple of additions to be found in italics, here is my current estimate of Arizona's 25-man roster on Opening Day 2010.