D-backs' Rotation Is the Key to Saving the Season
When the starting rotation performs to expectations, the Diamondbacks win.
The Diamondbacks still find themselves in a tough position regarding their deadline stance for 2025. They are under .500 at the time of this writing, at 45-46 and only 4.5 games out of a playoff position. However, their track record this season has never been an indicator of a true playoff contender.
Despite that, the team is only one run away from being right back in the race. They’ve shown the ability to beat better teams when they put it all together. When a starting pitcher records a quality start, the D-backs are 27-9 (.750). Despite their bad bullpen, Arizona has a better winning percentage when their starter performs to expectation than the rest of the league (.669). That in itself says something.
The D-backs have also recorded a quality start better than league average. On the season, they have 36 quality starts in 91 games (40%). That ranks ninth in baseball this season. While not as high as they would have hoped, considering the investment the team has put in their starting rotation, they’re getting good results.
There are both some positive and negative signs with the rotation. Zac Gallen is starting to put quality starts together, with two statement victories against NL West opponents. Ryne Nelson is proving his strong finish to 2024 was no fluke, once again stepping up to provide quality innings. Merrill Kelly has been the model of consistency for this rotation.
However, we also have to address that Eduardo Rodríguez and Brandon Pfaadt have not pitched up to standard. Rodríguez was supposed to provide veteran stability in the rotation, but has yet to deliver on an $80 million contract. He has the highest ERA in the rotation at 5.78 and the lowest quality start rate at 20%.
Pfaadt has the second-highest ERA at 5.42 and is still struggling to execute his pitches consistently. There are stretches where he does, and he looks good doing so, but he lacks the command to miss over the heart of the plate. In that area of the strike zone, opposing hitters are batting .335 with a .610 slugging percentage and a 65.6% hard-hit rate against Pfaadt.
Just two weeks ago, I wrote about how the rotation is a liability. In the 11 games since, the team is 4-7. However, that hasn’t been due to the rotation. In those 11 games, the rotation has pitched to a 4.19 ERA (13th) and a 3.07 FIP (5th). They have the second-best strikeout rate (28.8%) and the lowest walk rate (4.4%) in baseball in that stretch.
The question is, can they keep that up for at least another 15 games? If the answer is yes, it may be enough to convince Hazen to fortify a decimated bullpen. The D-backs lead the league in wins lost by the bullpen, tied with the Sacramento A’s at 14.
D-backs Under Review is Michael McDermott’s publication for deep analysis dives, game coverage, prospect coverage, and breaking down the biggest news topics involving the Arizona Diamondbacks. Michael has been writing about the D-backs since the 2015 season, with stops at AZ Snake Pit, Diamondbacks On SI, Venom Strikes, and Burn City Sports. He has covered over 40 MLB games at Chase Field and the Arizona Fall League.