Every season has the good and the bad, and 2026 was no different. The worst thing obviously was missing the playoffs despite winning 86 games. Goes without saying. But why did this team miss the playoffs? We as fans of the Arizona Diamondbacks are no strangers to missing the playoffs and having a whole laundry list of items to stew over for the offseason. However, I wanted to limit this list just like in my previous article to just the top 5 things. In order to do this in the most fair and balanced
way, I chose an analytical approach. I ranked the list of things that went wrong and tried to quantify each by WAR against preseason projections (Steamer and ZIPS average), or in other words what went wrong relative to expectations. So ladies and gentlemen, without further ado, here is stack ranked what went most wrong for the Dbacks in 2026:
1. The Projected Rotation Collapsed: 7.8 wins lost
This one is ugly. 4 of the 5 starters they planned around combined for about -0.6 WAR against 7.2 projected. This aspect of the team far and away takes the crown for the biggest thing that went wrong for the Arizona Diamondbacks in 2026. Merrill Kelly had the worst underlying numbers of any regular starter in baseball with an xERA and a K-BB% that both ranked dead last amongst qualified starters. And he took the ball every 5th day for 162 IP so those innings did real damage to this team.
Zac Gallen went from having an elite 4 seamer in 2023 (98th percentile by run value) to 8th percentile in 2026 at the same velocity. Hitters simply stopped chasing as the league adjusted to Gallen in a big way and Gallen has simply failed to make an adjustment back. Because he signed the big contract in the offseason, he got waaaay to much leash this season pitching 105 innings of 6.07 ERA baseball. Ouch.
Corbin Burnes was sold to the fanbase since spring training as someone who was going to come back and provide this team a real shot in the arm. The actual results? He basically didn’t even pitch logging just 10.1 innings and looking like he was most certainly rushed back too fast.
As a team, the starters allowed the 3rd hardest contact in MLB (xwOBA .341) and ranked 28th in K-BB% despite throwing the 5th most innings. Put plainly, if it wasn’t for Eduardo Rodriguez and Michael Soroka (+3.5 WAR over projection combined) this season would’ve been an absolute disaster. And to add even more doom and gloom, ERod’s 2.89 ERA came with a 4.27xERA (41 st percentile) so the Dbacks need to really do something this offseason with Soroka becoming a free agent to drastically sure up this rotation.
2. Dead AB’s at 1B, LF, and DH for half the season: about 5 wins lost
Lourdes Gurriel Jr, Max Kepler, Pavin Smith, and Carlos Santana were combined -5.4 WAR against projection. Gurriel alone was -1 WAR and add Adrian Del Castillo to the mix and that group took 665 PA below a 60 wRC+. Ouch. This group drug the team down so much that the offense went from 19th in runs per game before the break to 4th after the break and about 85% of that rise came from changing who batted. This was a massive miscalculation by Hazen and co. in the offseason when they built this team. Several people such as our good friend Jack Sommers called out in the offseason that this team badly needed an impact left handed bat this offseason.
However Hazen shrugged those concerns off when asked about them before the season started and it really came back to hurt this team. To make matters worse, the coaching staff was still trying to coach this group as if they were the thumpers from seasons before having them sell out for pulled fly balls and the result? Production on pulled fly balls and line drives ranked 30th or dead last in the league. Put another way, Hazen and co. constructed a lineup full of guys who lacked the pure bat speed to make the pull fly ball approach work, and the coaching staff continued to coach to it despite disastrous results. Yuck.
3. Marte’s Lost second half and the ‘big 3’s’ step back: about 2 wins vs expectations (about 7 vs 2025)
The chart below says it all. At least where Carroll and Perdomo fell flat with the bat they were able to add value on the bases and the field, however Ketel Marte was the real miss here (-1.9 WAR vs expectations). Marte’s chase rate jumped from 25% to 32% before any injury. After the all star break his xwOBA fell from .364 to .307 and his hard hit rate went from 45% to 36%. And that was aside from all of the extra negative attention he brought this team after the break which if I was in charge I’d add another -1 WAR for that alone! Carroll was close to his projection, although his swing got longer and loftier as the season went on and the pitchers just attacked it with more fastballs. His whiffs per swing on fastballs rose 3 straight years to 25.5% in 2026. He did begin to adjust in the second half as the fastball whiffs dropped down to 21.9% but his results simply didn’t follow. There is something to be optimistic about there at least.
4. Injuries Especially to the Arms
Now, I know what people will say, every team has injuries. And that is certainly true. The Dbacks actually had some good injury luck in 2026 relatively. However I have stuck to the plan this long taking an analytical approach and so I need to stay with it. If we look at the injuries from the standpoint of total IL days, the Dbacks actually ranked 6th most in MLB with 2,107 IL days. MLB median was about 1,660. Here is the list:
Not really that much to say here except for another year it seems like this team’s replacement depth got tested with guys like Mitch Bratt and Jose Cabrera pitching meaningful innings. Hazen and co need to anticipate these injuries rather than point to them as an excuse and build more depth into the organization so that when they happen, its more of a minor drop in production not production falling off a cliff. Expect injuries.
5. The Left Handed Core Stopped Hitting RHP and they Didn’t Acquire a Bat TWICE
You guys lnew this was coming. And it partly underlies #2 on this list. However, it was so bad, it definitely deserves its own spot. The overall read: This team went from being one of the best hitting teams against right handed pitching in the league to being one of the worst and finishing about 4 wins below average against righties. This matters so much because righties pitched against the Dbacks in 73% of their plate appearances. Against lefties, they were 2nd in MLB at +44 runs. The root cause of their offensive struggles is pretty simple.
What’s strange however is that the ‘big 3’ all bat left handed against righties and usually perform pretty well. The collapse of the ‘big 3’ against RHP is something that I don’t think anyone really saw coming in all fairness. So what happened to them? Here is the frustrating part: mostly bad luck. As a group, the lefties had a wOBA of .300 against an expected of .313. Marte and Carroll account for much of this bad luck however which is good news for 2027.
In addition to the core not producing against RHP, Hazen also whiffed on acquiring a left handed impact bat not once but twice. Before the season it felt more like hubris, at the trade deadline it came down to just more bad luck with multiple reported deals falling apart at the last minute due to medicals. Unfortunately it just seemed like destiny that this team was going to struggle against righties in 2026. Fortunately it appears as to most of that being due to bad luck so although this team definitely needs to acquire an impact left handed bat this offseason, they already have 3 who seemed to just get really unlucky all at once.
And so with that, let’s end this terrible exercise of doom and gloom with that little bit of optimism towards 2027!
