Neither Didi Gregorius nor Chris Owings were expected to be major contributors to the Diamondbacks coming in to this season, with a middle infield apparently largely set as Aaron Hill and a Cliff Pennington/Willie Bloomquist platoon. However, the baseball gods had other plans for the Diamondbacks, with both Hill and Bloomquist hitting the DL early, resulting in a swift call-up for Gregorius. He made his Arizona debut on April 18 in New York,, and hit the ground running, homering on the very first pitch he saw in a Diamondbacks uniform, off the Yankees' Phil Hughes.
Early on, Didi's offense proved far in excess of what his reputation has predicted. Over his first 30 games for us, he had a line of .328/.386/.534, for a .920 OPS. Obviously, that couldn't last, and in June Gregorius came back down to earth with a bump, posting only a .588 OPS. That was much closer to his performance the rest of the season, with his line in the 72 games Gregorius played after May being a much more pedestrian .218/.311/.298. Didi struggled particularly hard against left-handed pitching, hitting at the Uecker Line over 2013, and with an OPS against southpaws of only .512.
Owings spent most of the year in Reno, but earned himself a call-up when the rosters expanded at the beginning of September, and made his major-league debut on the 3rd against the Toronto Blue Jays. He got a fairly-decent look the rest of the way, starting the majority of the team's games down the stretch (13 of the last 23). Most of those were at shortstop, but interestingly, he was also given three starts at second-base - he had also played 11 times there when with Triple-A Reno, the first time he had occupied the position in his pro career.
Small sample size obviously applies, particularly for Owings. That said, this appears to indicate the advantage goes to him, but it's worth nothing that Chris's average was likely powered by a BABIP of .356. In turn, that was boosted by a line-drive rate of 29%, though you still have to wonder if that underlying driver is sustainable. Didi's numbers in the same categories were .290 and 23% respectively, both much closer to league-average, so it would seem his stats are likely a better projection of what we should expect going forward than Owings'. To try and address the sample-size issue, let's take a look at both men's numbers in the minor-leagues.
|Rk (2 seasons)||Rk||81||334||301||34||79||1||25||10||7||22||37||.262||.323||.312||.636|
|A (1 season)||A||120||548||501||65||137||5||41||16||7||33||62||.273||.327||.379||.706|
|A+ (3 seasons)||A+||75||306||284||42||81||5||30||8||8||13||40||.285||.318||.401||.719|
|AA (2 seasons)||AA||119||519||464||63||128||3||47||6||6||38||74||.276||.334||.379||.713|
|AAA (2 seasons)||AAA||55||235||216||32||57||8||25||1||2||14||32||.264||.307||.458||.766|
|Rk (1 season)||Rk||24||111||108||20||33||2||10||3||0||3||25||.306||.324||.426||.750|
|A (1 season)||A||62||271||255||39||76||5||28||1||3||9||50||.298||.323||.447||.770|
|A+ (2 seasons)||A+||180||812||762||118||206||22||74||18||7||28||193||.270||.302||.437||.739|
|AA (1 season)||AA||69||310||297||35||78||6||28||4||3||11||69||.263||.291||.377||.668|
|AAA (1 season)||AAA||125||575||546||104||180||12||81||20||7||22||99||.330||.359||.482||.841|
It's interesting to see how the OPS of Gregorius in the majors is almost identical to the number he posted over his entire minor-league career. That's somewhat concerning, because it's not normally the case, in part due to the higher level of pitching you face once you make it to the show.. For instance, if you look at Cliff Pennington, his minor OPS was .722, about sixty points higher than he has had in the majors. Owings does show something of a drop-off: that it's less than Pennington, is explained in part by the BABIP factors discussed above, though this is countered by the obvious boost this year from 125 games with Reno.
Worth noting that Owings is younger, by about 18 months, than Gregorius. He turned 22 about three weeks before his call-up. At the same age, Gregorius was still with Cincinnati, and more than half a season from being promoted out of Double-A. How much more improvement through aging there might be with Owings, is hard to say, but it would seem fair to conclude there's probably more scope for that than with Gregorius. On balance, I'd give the overall offensive edge to Owings.
This is even harder to evaluate, because there are few public metrics available for minor-leaguers, and the small sample size renders major-league ones almost useless, particularly for Owings, who saw only 93 innings at short, and thirty at second. Writing about Chris, Minor League Ball's John Sickels said: "He is a good athlete with a solid set of tools, featuring a strong throwing arm, enough speed to be a threat on the bases, and sufficient range to be a major league shortstop. He's not a gold glove, but he can handle the position." MLB's Bernie Pleskoff wrote, "His defense is much better than indicated by the 28 errors he made at Reno. He isn't flashy, but he gets the job done."
Gregorius is something of a question-mark. We've all seen him make some amazing plays, and there's no denying the cannon of an arm. But the defensive metrics haven't exactly been impressed by him thus far. Among shortstops with 800+ innings played this year, Didi was ranked 17th of 26 by UZR/150. No disaster, to be sure, and defensive numbers for barely half a season should always be taken with a grain of salt, but not much evidence that he's a great improvement over Owings. He also isn't really a candidate to move to second, because that would devalue the throwing arm which is arguably his best tool. This one is likely close to a tie.
Another factor to consider, is the question of which player would fit better with the others on the roster. One of the problems we saw this season, was that our two main shortstops, Gregorius and Pennington, were too similar. Both were defense-first players, who had severe trouble handling left-handed pitching. That isn't the kind of situation you want to have - you would prefer to have two players whose skill-sets mesh like jigsaw pieces, not overlapping so much. Pairing the right-handed Owings with Pennington would at least seem to give you a better chance for the platoon advantage. Though both this year and last in the minors, Owings hit RHP better than LHP. So, go figure.
The other point to ponder would be that other teams are likely carrying out similar evaluations of the two players. Player X may be "better", but that would likely also mean that Player X would be more in demand elsewhere, and so would probably bring a bigger return in a trade. But across 30 teams, the choice between Gregorius and Owings is not so obvious that there'll be unanimity. Ideally, you want to find the team that prefers Player Y instead - better yet, two teams, so there's a bidding war - and cash in on their interest. However, if that's Gregorius, will Kevin Towers be prepared to deal him away, less than a year after having traded for him?
Option H: Trade Aaron Hill and play both
The "nuclear option" is something we discussed last week: trading the long-term contract of Aaron Hill, and moving Owings across the other side of the infield, to provide a long-term solution at second-base. It would certainly make the team younger and cheaper, but Hill's offensive production at the position would be very difficult for Owings to reproduce. The prospect doesn't have much experience at second-base either. However, he didn't embarrass himself with his performance there in September - albeit in less than a handful of games - and the transition from shortstop to second base is something which should be possible, with effort.