Fixing the Diamondbacks: Open off-day discussion thread

The last home-stand saw the D-backs lost their first two series of the season, and they managed only one win among the seven contests. They now get an off-day, as the team heads out on the road, starting in New York against the Mets tomorrow. Let’s occupy ourselves with a brain-storming session about the team. Topics for you to consider should probably include the following

• How much of a problem is there?
• What can be done to improve the offense?
• How should we handle the back of the rotation?
• Is the humidor breaking the 2018 Diamondbacks?

Here are a few introductory thoughts on each of those topics.

How much of a problem is there?

The Diamondbacks still lead the National League West by two games over the Rockies. However, that’s largely because everyone in the division has been sucking of late: not one of the five teams has a winning record over the last ten games. After one of the best Aprils in franchise history, May has been severely disappointing: Arizona is currently 5-10, and will need a very strong road trip if they’re to have any chance of avoiding a losing record. All aspects of the game have taken a step back:

• Starters’ ERA - April 3.61, May 4.34
• Bullpen ERA - April 1.92, May 3.33
• Runs scored per game - April 4.71, May 2.53
• OPS - April .738, May .568

However, the counter-argument is that, overall, the team is still the best in the division. We have outscored the opposition by 18 runs, and are the only NL team with a positive run differential. Our Pythagorean projected record is just one game off our actual W-L, and the Baseball Prospectus standings show the D-backs as the best team by both second-order (projected runs we “should” have scored and allowed) and third-order (taking strength of schedule into account as well) wins. We knew this stretch of the calendar was going to be very tough.

What can be done to improve the offense?

Losing A.J. Pollock, probably the team’s MVP to this point, for 4-8 weeks is certainly a huge blow. But a bigger problem is likely the under-performance at the plate of a number of other players. With Pollock out, the only two position players with an OPS+ above 86 are David Peralta and Daniel Descalso - the latter, while great, is hitting so far above his career norms that it would be silly to expect it to continue. There is some reason to think park-adjusted metrics like OPS+ are undervaluing the D-backs, because they don’t take into account the (apparently brutal) impact of the humidor. But look simply at straight OPS. There are six D-backs with an OPS even of .700. That includes two pitchers and Pollock.

We will get Jake Lamb back, which should help. And I continue to believe that Paul Goldschmidt will turn the corner eventually, and will not hit .208 all season. Hopefully, new arrivals Steven Souza and Alex Avila will both also return to something nearer their career norms. And offense is down, all over baseball: the current MLB average of .246 is the lowest sine 1972. But is there something less passive which you feel the team should be addressing, to get the Arizona hitters performing better? What do you see as the problems with the team’s approach, and what are the solutions?

How should we handle the back of the rotation?

Madame Regression took Matt Koch into her dungeon for a lengthy session of strict discipline yesterday, adding Koch to the list of starting pitching issues. Zack Greinke and Corbin have been solid at the top of the rotation to date, but thereafter? Zack Godley has seen all his peripherals go in the wrong direction; Koch faced tough opposition and likely pitched better than we could have hoped; and we still don’t know who will pitch on Tuesday in Milwaukee, when the team next needs a fifth starter. Clay Buchholz and Taylor Clarke seem the main candidates, but neither have pitched in the majors this season - or, in the case of Clarke, ever.

Reinforcements for this department are on the horizon. Robbie Ray is progressing with his rehab from a strained oblique muscle, and Shelby Miller is also working his way back after Tommy John surgery - he threw 62 pitches in extended spring training this morning. However, there is no immediate timeline for either man, and even with some off-days in their future, the team will certainly need several starts from Koch and whoever becomes our #5 in the meantime. Is it perhaps worth trying T.J. McFarland as the fifth starter again? We all remember the disaster which was his outing in that role against the Twins last year, but his ERA this season is less than half what it was going into that game, and he has performed admirably when called upon for long relief roles, as yesterday showed.

Is the humidor breaking the 2018 Diamondbacks?

The Diamondbacks winning percentage is 109 points lower at him that it is on the road. This is not normal: much the same players, last season, were 136 points better at home. What has changed? The obvious answer is the humidor. Now, obviously, the humidor in itself will be neutral: all balls will be equally moist [TWSS]. But not all teams are equal, and things like fly-ball rate (for pitchers) or launch angle (for hitters) will play into how much of an impact the humidored balls have. There’s no doubt that offense is down dramatically at Chase Field this season: overall, OPS has dropped from the 2017 figure of to a figure this year of .776 to .645. But for whatever reason, this has impacted Arizona more than their opponents.

All told, the D-backs have both hit and allowed 44 home-runs. However, the splits paint a picture that’s far from equivalent. At Chase, the Diamondbacks have been out-homered in their home-park by a margin of 31-18. Conversely, on the road, they have out-homered their opponents, 26-13. We hit 97 points better on the road, while our opponents drop only by 14 points at Chase compared to their parks, even discounting the home-field advantage. There’s a long tradition of franchises working the park to suit their team, and planning their team to suit the park. The question has to be asked: is this an area where Mike Hazen and co have messed up, and not planned appropriately for the humidor effect?