Comparing the Diamondbacks this year and last - Part 1: around the diamond

With nine games left to play, the Diamondbacks sit at 78-75. If they post a winning record over the rest of the schedule, six against the Padres and three against the Cardinals, they will surpass last year’s 82-80 record. Arizona would need to go 3-6 down the stretch to end with a lower winning percentage. It’s already at least somewhat in excess of most people’s pre-season expectations. When we polled people before the season, almost two-thirds (63%) predicted 79 wins or fewer in 2019.

That’s understandable. Over the winter, the D-backs had lost the best position player in franchise history, Paul Goldschmidt, as well as Patrick Corbin, A.J. Pollock and Mr. Clutch, Daniel Descalso. Then, at the trade deadline, Mike Hazen dealt their best starting pitcher, Zack Greinke, to the Houston Astros. Given the amount of WAR no longer present, it’s definitely an achievement that the team was still contending for a wild-card spot until the final month of the season. But how did they manage it?

This and next Thursday, I’m going to take a look at how the team stacks up compared to last year’s model. Next week, I’ll break it down by players: those who left, those who arrived, and those whose performance changed (for better or worse) between 2018 and 2019. But I’m starting by comparing the overall production around the diamond. The metric of choice is Baseball Reference’s WAR, and in particular their summary of Wins Above Average By Position. The chart below compares the D-backs at each spot, this year and last: 2018 performance is in blue, and 2019 in red.

All told, the Diamondbacks currently sit at 4.5 wins above average (WAA), which is two wins better than they were through the end of last season. That seems about right: even ignoring wins, with nine games left, Arizona’s run differential is +55, a little bit ahead of the +49 posted over all 162 contests in 2018. But let’s break it down, and see how the numbers compare at each spot on the diamond. For each position, the first number is the 2018 production by WAA, and the second is the WAA for 2019.

SP: 3.9 vs. 2.7

• 2018 Opening Day rotation: Patrick Corbin, Robbie Ray, Zack Greinke, Taijuan Walker, Zack Godley
• 2019 Opening Day rotation: Greinke, Ray, Godley, Luke Weaver, Merrill Kelly
• 2019 current rotation: Ray, Alex Young, Mike Leake, Kelly, Zac Gallen

That’s a startling degree of churn, with Ray the only survivor from a year and a half ago, and even a 60% change since Opening Day this season. Given the departure of Corbin, loss of Walker, and half a season of Greinke, this number has stood up pretty well, I’d say. Arizona has had 69 starts from rookies, and have three (Clarke, Kelly and Young) making double-digit starts for the first time ever.

RP: -2.4 vs. -4.1

I’m a bit surprised to see this year’s bullpen significantly worse than last season by this metric, but there does seem something a bit funky with bWAR, as the Cubs and Cardinals are the only teams with bullpen WAA above zero. That said, of our total pitching bWAR of 10.7, the top six spots belong to starters, who have combined for 11.1 bWAR, so do the math. It’ll be interesting to see how Hazen handles the bullpen this winter, after the abject failure of the Greg Holland experience. Do we go for another bargain-basement free-agent as our closer, or use one of the in-house options? The problem with the latter is volatility: almost all potential candidates have had their share of rough patches.

C: -2.1 vs. 0.9

Sometimes, simply “not sucking” is enough for a palpable improvement. That’s the case at catcher, where the three-headed experiment from last year was abandoned, replaced by a more regular pairing, of Carson Kelly and Alex Avila. This is one area which would probably have looked considerably better at the end of July, when Kelly’s OPS for the year was .911 - he has hit .176 since, with an OPS of .650. It’s hard to be sure how their work behind the plate factors into this number: though no Jeff Mathis (then again, who is?), both Kelly and Avila grade out as slightly better than average defensively over at Baseball Prospectus.

1B: 3.0 vs. 0.1

Christian Walker and Paul Goldschmidt have been a lot closer in value this year than anyone would have expected (currently 2.4 vs. 2.7 bWAR, in Goldy’s favor). But that’s as much due to a sharp downtick in Goldschmidt, who is currently exactly half as valuable as he was in 2018. In comparison to this year’s model, Walker has undeniably been serviceable enough for Arizona, and at a fraction of the cost. It is equally clearly a cut below the MVP-caliber production Paul provided for the Diamondbacks last season. However, I think before the season started, we’d all have been happy to settle for first-base being at league-average in terms of production.

2B: 0.8 vs. 1.8

This has been the most in-flux of positions for Arizona, no-one having more playing-time than Marte’s 224 PA there. Wilmer Flores (212) has seen almost the same, with the similar balance divided between Eduardo Escobar (119) and Ildemaro Vargas (136). Flores missing 50 games is likely a factor in the split, and he would likely have seen the bulk of time, if not quite reaching “everyday” status. He has destroyed left-handed pitching this year, hitting it at a 1.012 OPS clip, 287 points better than his figure against RHP, and it’ll be interesting to see what he does, good health permitting, over a full season in 2020. The $6m team option seems like a no-brainer at this point.

3B: -0.5 vs. 1.2

Dare I suggest that the injury to Jake Lamb might have ended up being a positive for the Diamondbacks this year? It allowed Christian Walker to fulfill his potential and play regularly at first-base, and Escobar to do the same at the hot corner. It’s not as if Lamb’s career platoon chasm has been greatly missed this year, since the switch-hitting Eduardo has batted .311 against southpaws. Jake, however, has been unable to hit even right-handed pitching in 2019, with a triple slash there of .182/.315/.297. That’s not good, and the specter of a potential non-tender this winter is looming over one of the longest-tenured members of the team.

SS: 1.5 vs. 2.8

This was already a position of strength for Arizona, thanks to Nick Ahmed’s Gold Glove defense. That has been sustained, but his value been helped overall by Ahmed’s improvement at the plate. It’s amusing, and quite interesting, to look at some of the prospect reports on Ahmed. While there’s nothing quite like a certain “fringy bat speed” comment that lives in infamy, we did get “multiple scouts said .240 with 8 homers is what you’re hoping for.” Not far off on the batting average. But those multiple scouts would be amazed to be told that Ahmed has a shot at only the third twenty-homer season by an Arizona shortstop. [Previously Stephen Drew hit 21 in 2008, and Jay Bell 20 in 1998]

LF: 1.5 vs. 0.0

It has been a rough year for David Peralta, who followed up his breakout season in 2018, by an injury-plagued one which ended shy of a hundred games. Things were going well through mid-May, but after he went on the IL, he never seemed right, batting .241 the rest of the way, compared to .309 to that point. Replacing him was a stew of Tim Locastro (OPS+ 83), Josh Rojas (75) and Jarrod Dyson (69), so while the defense may have been solid, and the HBPs positively off the charts, you can see why the overall output was no better than average.

CF: 0.3 vs. 2.4

The long-term contract extension given to Marte in March 2018 seemed something of a risk, considering he had been worth 3.7 WAR over his first 249 games. But it now looks a steal, for Ketel almost matched that production in 2018 (3.3), then more than doubled it again in 2019 (6.9), despite having to learn a new position this year. No surprise that center field proved the biggest source of improvement on the 2019 D-backs, going from merely average under A.J. Pollock, to the best in the National League with Marte. Useful backup here was provided by Dyson, who benefited from better health this year. His speed proved a useful addition to the team, both offensively and defensively.

RF: -2.3 vs. -1.9

Taking over from catcher as the biggest problem on the position side this year, we find right-field. Obviously, the injury before the season to Steven Souza didn’t help matters, though it was fortunate the team had signed veteran Adam Jones just a couple of weeks earlier. For all his clubhouse character, Jones has not really produced much, with an OPS+ of 86, his lowest figure in more than a decade. Still at $3 million, it’s hard to complain too much, even though he’ll likely pocket a good chunk more in incentives (up to a maximum of $2 million). Souza will be in his final year of arbitration eligibility next year, and the team will have to decide whether or not to roll the dice on him, one more time.