Image: Matt Kartozian-USA TODAY Sports

Spring isn’t all sunshine when it comes to battling for a spot on a 25-man roster for players, either.

The D’backs starting lineup is pretty much set heading into 2013 meaning the battles will be in the back end of the rotation, the bullpen and on the bench.

Miguel Montero, Paul Goldschmidt, Aaron Hill, Martin Prado, Chad Pennington, Gerardo Parra, Jason Kubel, Adam Eaton, Cody Ross and Willie Bloomquist are locks along with Ian Kennedy, Trevor Cahill, Brandon McCarthy and Wade Miley in the rotation. In the bullpen, JJ Putz, Heath Bell, David Hernandez and Brad Ziegler are also pretty much assured spots.

With the D’backs likely to carry 12 pitchers that leaves one starter, three reliever spots and three bench spots open.

Starting spot battle: Tyler Skaggs vs. Randall Delgado

Delgado was acquired in the Justin Upton trade along with Martin Prado. Delgado is probably projected for a back-end starter for his career and has solid stretches throughout his career so far. He owns a career 3.95 ERA over 127.2 innings in the majors. Skaggs has been a top-tier pitching prospect for a few years and appears to be ready to pitch a full season in the bigs. Skaggs owns a career 2.98 minor-league ERA. He did struggle a bit in his brief appearance with the D’backs last season with a 5.83 ERA over 29.1 innings.

Edge: Skaggs

Three bullpen spots: Patrick Corbin vs. Tony Sipp vs. Matt Reynolds vs. Josh Collmenter

Sipp and Reynolds have each spent quality time in the majors with solid results. Sipp has thrown 220.1 innings over the past four seasons with a 3.68 ERA and Reynolds has thrown 126 innings over the past three seasons with a 3.93 ERA. Reynolds and Sipp, both lefties, are solid bets to make the bullpen.

That leaves the final spot for Corbin and Collmenter to battle it out. Corbin is also a leftie and was effective over long stretches in the beginning of last season but then struggled down the stretch. Collmenter on the other hand, struggled mightily early and then picked it up as the season progressed. Edge: Collmenter

Bench Spots:

Back up catcher – Wil Nieves vs. Rod Barajas

Nieves was productive in limited time with both the D’backs and Rockies last season, hitting .301/.330/.410 over 89 plate appearances. On the other hand, Barajas was pretty awful in 321 plate appearances for the Pirates in 2012. He hit .206/.283/.343 for the season.

Edge: Nieves

With an outfielder and a utility player in Bloomquist on the bench already, the D’backs have some flexibility in the two remaining bench spots: Eric Chavez vs. John McDonald vs. Tony Campana vs. A.J. Pollock vs. Matthew Davidson

Edge: Chavez and McDonald

Sept. 18, 2012; Phoenix, AZ, USA; Arizona Diamondbacks starting pitcher Ian Kennedy (31) looks on during the first inning against the San Diego Padres at Chase Field. Mandatory Credit: Matt Kartozian-USA TODAY Sports

Kennedy was among three pitchers inked today. Relievers Brad Ziegler and Tony Sipp also signed on the dotted line as did third baseman Chris Johnson.

Kennedy is coming off a season that fell below his expectations. He finished with a 15-12 record and an ERA of 4.02. The 28-year-old right-hander has 36 wins in the last two seasons, tops in the National League during that span.

August 16, 2012; St. Louis, MO. USA; Arizona Diamondbacks relief pitcher Brad Ziegler (29) throws during the seventh inning against the St. Louis Cardinals at Busch Stadium. The Diamondbacks won 2-1. Mandatory Credit: Jeff Curry-USA TODAY Sports

Ziegler was a critical piece of the D’backs bullpen last season. The 33-year-old reliever had a career year last season, making 77 appearances, netting a career high six wins, pitching in a career high 68.2 innings and posting a staff best ERA of 2.49 . According to a tweet by Fox Sports Arizona’s Jack Magruder, Ziegler will be paid $3.15 million this season, a hefty raise from the $1.795 million he made last season.

Sipp pitched for the Cleveland Indians last season and was acquired by Arizona on Dec. 10th in the Trevor Bauer deal. He pitched in 63 games with the tribe posting a 1-2 record with a 4.42 ERA and one save. According to NBCSports.com, the 29-year-old left-hander will be making $1.275 million in the desert this season.

Johnson hit .281 with 15 home runs and 76 RBI’s in 136 games split between Houston and Arizona. The third baseman will be in a dogfight for playing time with Eric Chavez and Willie Bloomquist. Terms of Johnson’s deal were not disclosed.