It would be a stretch to call the Arizona Diamondbacks “good” over the last decade. But there’s one thing no team in baseball has been better at in that span: defense.

In fact, it’s not even close. From 2010 through 2019, the Arizona Diamondbacks posted 445 defensive runs saved (DRS). This suggests that, in the 2010s, the D-backs’ defense prevented 445 more runs than an average defense. The second highest DRS mark in that span belongs to the Boston Red Sox with 274 DRS.

Unfortunately, the team’s run of defensive prowess took a turn for the worse last year. The 2020 D-backs posted –2 DRS. In 2021, it’s been a complete disaster: –48 DRS, which is 28th in the majors and worst in franchise history. What happened?

It’s not exactly rocket science. For starters, the D-backs have played four different players at catcher, seven at first base, nine at second base, seven at shortstop, nine at third base, ten in right field, eight in center and 11 in left. 

In total, they have used 28 position players at 65 positions. For reference, the 2021 Dodgers have used 24 position players at 37 positions. 

The D-backs are pushing their defensive versatility to the max, with guys like Daulton Varsho, Josh Rojas and Pavin Smith all seeing significant time at four or more positions.

Defensive versatility, of course, is not bad. But there’s a big difference between taking advantage of a versatile roster and forcing players to play positions they are not well suited for. The D-backs fall in the latter category.

The question remains, though: how did they get to –48 DRS?

Before we proceed, it’s worth pointing out that defensive metrics like DRS are still a work in progress, particularly over small samples with individual players. With that in mind, we’ll focus on the extremes, where DRS numbers are more meaningful.

To start, here is a breakdown of the D-backs’ 2021 DRS totals by position.

Position	DRS
C	–2 (18th)
1B	4 (9th)
2B	–18 (30th)
3B	–5 (21st)
SS	–2 (21st)
LF	0 (16th)
CF	–25 (30th)
RF	2 (11th)

Several positions immediately stand out.

Second Base

The D-backs don’t have a Gold Glove winner at second base, but a dead last ranking here is initially surprising.

The D-backs have used nine players at second, and according to DRS, virtually all of them grade out below average. However, the sample sizes are so small across the board that it’s hard to blame any player in particular. Well, except for one…

That player is Andrew Young. Young has posted a startling –10 DRS in just 138 innings of second base defense. For those wondering why Young has struggled to stay in the big leagues, this is why. His range is very limited, and the numbers bear that out.

Third Base

The team’s –5 DRS at third base isn’t good, but it also isn’t particularly alarming over less than a full season. 

However, it should be noted that the bulk of the innings at third base (nearly 75%) have gone  to the recently departed Asdrubal Cabrera and Eduardo Escobar. Those two combined for a respectable 2 DRS in more than 900 innings.

The remaining group has posted a lackluster –7 DRS. The samples are too small to point to specific players, but that total isn’t surprising. Since the D-backs moved on from Cabrera and Escobar, they really haven’t had a true third baseman on the roster, other than perhaps the recently demoted Drew Ellis.

Shortstop

What was a position of strength appears to be no longer. Does this mean Nick Ahmed’s run as an elite shortstop is over? Not necessarily.

Ahmed is currently eighth in baseball among shortstops with 5 DRS. Baseball Savant’s Outs Above Average (OAA) metric likes him even more. He leads all shortstops with 19 OAA. So what’s the problem?

Only about 79% of the D-backs’ innings at shortstop have gone to Ahmed. The bulk of the remaining innings have gone to the aforementioned Rojas, and according to DRS, they have not gone well. Again, we need to be really careful about small sample sizes, but Rojas’ –9 DRS in 239 innings is significant. 

Granted, it’s rare to find a utility guy like Rojas who can genuinely play shortstop well. He still provides plenty of value at second base, third base and the outfielder corners. Ideally, he should probably stay at those positions.

Center Field

This is where the D-backs have really had problems. Unsurprisingly, Varsho and Smith – neither of whom were particularly known for their defensive prowess coming up through the minors – have not fared well in their limited time in center. Varsho has posted –3 DRS in 149.1 innings, and Smith has posted –10 DRS in 252 innings.

What is surprising, though, is Ketel Marte’s –15 DRS in 567.1 innings. Marte has said repeatedly that he prefers playing second base, and Manager Torey Lovullo has granted that wish more frequently of late. It’s probably a good idea to keep Marte at second base into the future – both for his health, and because he may not be a great defensive center fielder anyway.

The Rest

The remaining positions – catcher, first base and the outfield corners – show few surprises.

Carson Kelly grades out as the team’s best overall defensive catcher. Varsho has thrown out 35% of attempted base stealers to Kelly’s 23%, but Kelly is a significantly better pitch framer.

At first base, former Gold Glove finalist Christian Walker still grades out well defensively, and Smith seems to be fine there too. 

In the outfielder corners, Varsho has posted a respectable total of 5 DRS. The rest of the team has been mediocre.

Conclusion

So, how do the D-backs avoid another disastrous season defensively? Here are a few main takeaways:

• Move Marte to second base, and avoid playing Young at 2B (or get him to the point where he can)
• Ensure the team has a true third baseman entering the season to pair with current options like Rojas, Ellis and Josh VanMeter.
• Play Ahmed as much as possible at shortstop, minimizing time given to fringey utility options like Rojas.
• Find a new everyday center fielder via free agency, trade or minor league call-up

Of course, all of this is easier said than done. 

The center field free agent market is barren, and top prospect Alek Thomas will probably take some time to adjust to the majors. Also, with the team likely not contending in 2022, the D-backs will probably choose to continue experimenting with several of their younger players, like Varsho in center field.

But coming off the worst defensive season in franchise history, the D-backs need to make some big changes. Their defense can really only go up from here.