While the main focus in the offseason should come down to pitching, one of the biggest questions that needs to be answered is who plays shortstop. The Diamondbacks have two candidates in Nick Ahmed and Chris Owings. Ahmed is a glove-first player that you hope breaks even as a hitter whereas Owings is a bat-first player that you hope breaks even as a defender. Whoever the team sticks with out of camp should be the everyday starter unless an injury or improvement in an area of weakness by the other.
The case for Nick Ahmed: Shortstop is a historically defense-first position. The Diamondbacks have very potent bats in their lineup they can hide Ahmed behind. In 2015, Ahmed at a replacement level bat posted 2.5 bWAR, which is more than acceptable for the Dbacks. He's never going to hit league average, but at a 70 or better OPS+ Ahmed's glove alone makes him a 2.0 WAR player. With the Diamondbacks struggles on the mound, it may be the best decision to put the best defense on the field possible after watching the 2016 team make laughable attempts to defend batted balls.
The case against Nick Ahmed: Ahmed is coming off back-to-back seasons where an injured hip has ended his season. In 2015, he posted a 70 OPS+, and he isn't going to hit for league average. For a player whose value is purely from the glove, any signficant decline in defense puts him in the Yasmany Tomas category of useless. Chris Owings swings a better bat and runs the bases better, should the Diamondbacks opt for a more offensive option.
The case for Chris Owings: Chris Owings is clearly the superior bat and baserunner of the two. In 2016, Owings has hit around league average with an OPS+ of 96. While Owings doesn't have the range or arm that Ahmed has, he is still dependable on converting the batted balls he can get to into outs. Owings is one of the best middle infielders in turning the double play at short, as his double play runs cancels out the negative value in defense. As of today, Owings has been 2 runs above average, both coming from his baserunning skills. An average MLB player is certainly not a bad player to put in the lineup, especially since Owings has cut down on the strikeouts.
The case against Chris Owings: The biggest problem in 2016 was defense with AJ Pollock and Nick Ahmed missing a lot of time. Owings is an average at best defender at shortstop with below average range and an average arm for the position. While Owings is a more consistent bat, the difference in defensive runs saved (DRS) is 25+ runs. Owings' bat and baserunning doesn't make up the difference, even if Ahmed posts an OPS+ in the 60s. Another issue is whether Owings can repeat his batting line from 2016, as it's a result of a .342 BABIP. Looking at his batted ball profile from the past and in 2016, Owings might not sustain .340, but .325-.335 is definitely reasonable.
Verdict: I'm more biased towards defense than offense and players who can contribute without having to swing the bat. So I like Ahmed at SS as the starter. That doesn't mean Owings doesn't have some sort of utility to the club, as while he's not a Gold Glover he isn't a liability in the field either. Owings has a good enough profile on offense to play everyday, so perhaps the team should look into him as a super utility player since everyone can't play everyday.