SCOTTSDALE, Ariz. -- As spring training enters its final week Monday, the fifth spot in the Diamondbacks' starting rotation remains probably the team's biggest unanswered question.
The competition between left-hander Patrick Corbin and right-hander Randall Delgado has, however, seen a bit of separation after the pair's back-to-back starts Friday and Saturday, and it appears Corbin is in prime position to win the job.
For his part, Corbin feels he's done all he can to show the team he's worthy of the final rotation spot and isn't worrying too much about the looming decision.
"My goal now is to get ready for the season," Corbin said after his start Friday night. "I feel I've done everything they've asked. I feel that if they pick me for that spot, I can go out there and compete."
Against the Indians on Friday, Corbin allowed two runs on three hits over five innings. It was just his latest impressive showing. In 19 23 innings over six Cactus League appearances, Corbin has a 3.66 ERA, 19 strikeouts and seven walks.
Corbin, 23, also has an advantage over Delgado, also 23, in his track record with the D-backs. While Delgado was acquired from the Braves in December as part of the Justin Upton rade, Corbin has already made 17 starts for the D-backs, all last season. That history and Corbin's left-handedness -- the D-backs have said that they'd prefer a second left in the rotation to go along with Wade Miley -- will undoubtedly factor into the team's decision.
A decision could come at any time, as manager Kirk Gibson suggested Sunday that the team is getting ready to make some moves, but it could also go until the end of spring training, with each pitcher getting one more start.
Either way, general manager Kevin Towers will have a heavy hand in the decision, probably even the final say.
"It's a process, and we won't make that decision until KT's ready to make that decision," Gibson said Saturday. "Ultimately it's his call when it's time to make the decision, and we as a group will make that decision.
"Ultimately, he is the GM. If he wants Joe Blow to be that guy, he's going to be that guy. That's not how it works, but we communicate throughout the process."
Pitching coach Charles Nagy also will be involved in the decision.
Delgado may have fallen out of the race with his rough start Saturday in Surprise. Against the Royals, Delgado gave up six runs on nine hits, including three home runs, and issued four walks. Gibson said afterward that Delgado just wasn't hitting his spots the way he needed to.
"He was on and off," Gibson said. "He actually had some good innings, and then he had a couple walks, got himself in trouble with the bunts. He's got to be more consistent."
Delgado had impressed enough in previous two starts that the competition appeared almost dead even. In those two starts combined, he allowed two runs on nine hits in nine innings. After Saturday's setback, Delgado is 2-1 with a 6.88 ERA, six walks and 10 strikeouts over 17 innings this spring.
Complicating the decision a bit is Wade Miley's health. The left-hander pitched in a game Sunday for the first time since being scratched with biceps discomfort March 12. He pitched 3 13 innings and allowed four runs on six hits, including two home runs. He said afterward that he felt no discomfort and believed he'd be ready to start the season normally.
As long as Miley is healthy, there will be just one spot available, even if the D-backs use an off day to skip Miley the first time through the rotation. That appears to be the most likely scenario at this point.
Delgado may or may not get another start, with a good one at the very least making the D-backs' decision harder. But right now, it looks like Corbin will break camp with the major league team for the first time in his career.
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