The Arizona Diamondbacks have a deep rotation heading into the 2013 season. The top four spots, in no particular order, are comprised by Ian Kennedy, Trevor Cahill, Daniel Hudson and Wade Miley. After those four, there are three young guys who will be given the shot at the No. 5 spot.
Lefties Patrick Corbin and Tyler Skaggs, along with Trevor Bauer, will likely be given every opportunity in Spring Training to win the job. Prior to Spring Training, though, it's useful to look at who has the upper hand.
Corbin likely has the early lead in the competition. He had the most major league experience of the three last season, appearing in 22 games and starting 17 of them. He put together a 6-8 record with an ERA of 4.54 over 107 innings pitched. Corbin was very hittable, however. Opposing batters hit .280 against him with 14 home runs. He'll have to learn to miss bats as he progresses.
Skaggs likely has the best stuff of the trio, though that didn't lead to success in his only stint in the majors last season. In six appearances—all of which were starts—Skaggs posted a 1-3 record with an inflated ERA of 5.83. That came over 29.1 innings. Skaggs put a ton of runners on in his brief stint, producing a WHIP of 1.47. Much of that comes from inexperience and the fact that he was adjusting his stuff to major league talent.
Bauer, assuming he's even on the team come Spring Training, will also be given a shot. He wasn't very good in his four starts last season, pitching to a 6.06 ERA in 16.1 innings. His WHIP of 1.65 has much to do with him allowing 11 earned runs (13 total) during his starts. Bauer looks like the third option at this point. His standing with the organization is in question, and he was the least impressive of the trio last season.
In my opinion, Corbin should be the No. 5 starter. He has the most experience and was the most effective in 2012. It may make the rotation a little lefty-heavy with Miley also being a left-hander, but that will work to neutralize the left-handed batters in the National League West.
All three pitchers have bright futures ahead of them. Corbin just seems to be the furthest along in his development at this point.