The Diamondbacks system as a whole lacks the impact talent in the farm, although they do have a lot of impact talent under the age of 26 that have already debuted. This list does not include players that have already debuted with the team through 2016.
LHP Jared Miller: A move to the bullpen combined with the addition of a cutter to his repertoire has really rescued Miller’s career. After converting to a relief role, Miller dominated the two A-ball levels before getting looks at both AA Mobile and AAA Reno. Over 61 1⁄3 IP, Miller struck out 80 and walked 20. Kane County pitching coach Rich Sauveur deserves a lot of credit for helping Miller learn the cutter. Miller had a 36/13 strikeout to walk ratio in 26 1⁄3 IP in his longest stop at AA Mobile. The strong season put him on the Fall League roster, where he’s gotten even better. So far, Miller has faced 18 hitters, gotten 16 outs, and has struck out 12. With the season he’s having, you have to include him in the mix for a relief spot in Spring.
LHP Anthony Banda: Banda has had a solid run since getting moved to the Diamondbacks system in July 2014. All he had left to do was prove it in the upper levels of the minor leagues, which he did in 2016. Banda is a strike-throwing, ground ball pitcher that will eat up innings. The only worry I see in his numbers is that his strikeout rate declined to the levels pre-trade in AAA Reno, although the walk rate has been fairly consistent all season. There’s little fine-tuning left in his game between now and his eventual debut, so he does deserve an equal shot at a rotation spot this Spring as everyone else. If he’s able to post the strikeout and walk rates he had in Visalia and Mobile, he should be a solid #4.
INF Jack Reinheimer: The Diamondbacks have a spot open for a utility infielder plus I do think that the team can look to do better than Phil Gosselin at the position. Reinheimer profiles as a utility guy, but has more value than Gosselin defensively due to his ability to play shortstop and second base better. Reinheimer doesn’t offer much in the power department, but has solid discipline at the plate, makes contact, is a terrific base stealer and a solid defender at SS. Since Gosselin and Reinheimer both have options remaining, there’s no reason to be forced to make one decision or the other although Gosselin is more used to coming off the bench than Reinheimer, who’s played every day in the minors.
RHP Taylor Clarke: I don’t expect Clarke to make the rotation out of Spring, considering he has very little experience dealing with strong hitting environments. He should be put on the big league camp roster as a non-roster guy just to see what he has and how far he needs to go in order to make the majors. As a pitcher, Clarke has a pretty high floor as a command-control guy that doesn’t walk hitters and keeps the ball in the yard despite being a fly ball pitcher. The fly ball tendency is something worth monitoring when he’s in AAA Reno to see if the fly balls turn into homers or are of the variety that turn into outs. I wouldn’t be surprised if he suits up for the team by September, he’s on a similar track to Aaron Blair two seasons ago.
INF Domingo Leyba: Given the team’s problems at the shortstop position (Owings doesn’t have enough range or arm to stick, Ahmed doesn’t produce enough at the plate), the Diamondbacks could be looking at a pair of infielders on the farm team. The elder prospect is Jack Reinheimer, who profiles better with the glove than Leyba, who has a more potent bat. Leyba is very young, having just turned 21 in September. Leyba had a strong 2016 season in Visalia where the bat started producing more extra base hits and doubling his walk rate to put up a .294/.346/.426 slash. After a promotion to AA Mobile, the walk rate jumped to nearly 10%, the strikeout rate decreasing to 12.6%, and no change in ISO. That produced a .301/.374/.436 slash despite a 10 point drop in BABIP. If Leyba doesn’t have the range to play an above average SS, it may make more sense to keep him long term as the team’s 2B of the future.
INF Jamie Westbrook: Westbrook looked poised to be the team’s 2B of the future following a breakout 2015 campaign where he slashed .319/.357/.510 for the Visalia Rawhide. 2016 has put a damper on those thoughts, as Westbrook suffered from a significant power outage and possibly rotten batted ball luck as he posted a .294 BABIP. The strikeout and walk rates were pretty consistent from where they were the previous season, so plate discipline isn’t the likely problem. A strong start in 2017 could be what he needs to break through and get promoted to the next level in AAA Reno. One noticeable trend is his wRC+ is well over 100 in hitter-friendly leagues and under 100 in pitcher-friendly leagues, although the trend is 130 vs. 95.
RHP Jimmie Sherfy: Sherfy’s career resurrected with a strong 2016 campaign in both Visalia and Mobile. After two years of struggling in Mobile, Sherfy came back with a vengeance and was one of the best relievers in the Southern League before getting a promotion to Reno. In Reno, Sherfy had a decent first couple weeks, but got a hard lesson in how hitter-friendly the PCL is with a horrible final month of the season. The strides he made April-July shouldn’t be discounted as the late collapse could have been just fatigue. Sherfy was unhittable with a .168 BA against and a 79/24 K/BB in 55 1⁄3 IP with 30 saves. While I don’t think he starts the season on the MLB roster, how he performs in his 2nd go in Reno will be very interesting to monitor.