Here are stats for the nine who appear to have a shot at rotation spots, based on their usage patterns so far. I've divided them into groups of three. First, there are the "Definites" - Zack Greinke, Patrick Corbin and Shelby Miller, who could get shelled from now until Opening Day, and still have a spot. Then there are the "Possibles" - Rubby De La Rosa, Robbie Ray and Archie Bradley, from whom the two remaining spots are most likely to be drawn. And finally, a trio of "Long shots" - Tyler Wagner, Zack Godley and Yoan Lopez, [I didn't include Braden Shipley, as he has only thrown one inning in each of his appearances, and so doesn't even seem to be being considered]
Thus far I'd say that Ray and De La Rosa are most likely to make the rotation. There were legitimate question-marks over Rubby's performance in his first two outings, but the one earlier today at Salt River Fields will have gone quite some way to assuage those doubts. Mind you, this has always been De La Rosa's style: he'll look terrible one game, and be absolutely unhittable the next. Still, on the basis you are only as good as your last start, he has probably taken an edge over Bradley at this point. If that continues, it will avoid the team having to answer shoewizard's awkward question about whether or not they have the "guts" to pull the plug on Rubby!
However, it is certainly Ray who has been the most consistently impressive of the contenders for back end rotation spots, and it will be interesting to see whether that continues into his third start at Camelback Ranch tomorrow. I also note that all three of the "Possibles" appear to have been trying rather harder than the "Definites". The former have racked up 19 strikeouts in their 20.2 innings, while the almost-certain top three guys in our rotation have only six strikeouts over 15 innings. Indeed, Shelby Miller is still looking for his first K. This makes total sense: they can tinker with pitches, or try new stuff out, because they don't have to impress anybody or "win" a spot.
Arguably, you could throw Godley into the "Possibles" group, as his K:BB ratio is closer to being in line with them than Wagner or Lopez, and he is clearly giving it his all. Thus far though, Godley still appears to be on the fringes, albeit probably higher on our depth chart than the other two. It has been nice to see Lopez throwing relatively effectively. Small sample size certainly, but no walks in four innings is definitely an improvement over the 24 walks in 48 innings he posted for Mobile last year. Wagner's numbers thus far, with as many walks as strikeouts, haven't done anything to boost his stock.
All told, I've been happy with the early spring performances here. Taking the top six, their combined line to date is:
Rotation: 35.2 IP, 42 H, 14 R, 12 ER, 7 BB, 25 K, 3.03 ERA
I would be more than happy to take that from our starting pitchers during the regular season, though I should express the caveat that pitchers are generally regarded as being "ahead" of hitters during the early part of spring training, because they've been actively engaged for longer. Keep this up, lengthen the outings and - of course - stay healthy over the next few weeks. That's all any fan can ask for from our starting pitchers in spring.