There are some safe assumptions, such as the Diamondbacks’ defense will improve significantly. Making safe assumptions will not reveal whether the Diamondbacks are on-track.
More insightful are two assumptions
with uncertainty that can be tracked during next season:
- Pitching will improve.
- Offense will continue near the record-breaking pace of 2024.
Tracking Pitching.
Obvious statistics like ERA lack the game-specific flavor that seems important to me.
In 2025, Torey Lovullo had great results with his bullpen in games with quality starts per this AZ Snake Pit article. My view is that he can do it again in 2026.
Let’s look at quality starts in the seven seasons when the Diamondbacks reached the playoffs, plus the last two seasons. From 1999 to 2017, when they reached the playoffs, the Diamondbacks had 82 or more quality starts. In the last three seasons, they had significantly less quality starts (between 55 and 68).
The first statistic to track is quality starts in at least 50% of games played.
The next observation is that when the Diamondbacks (pitchers and defense) allowed 6 or more runs in 2025, they only won 11.9% of their games. In 1999 to 2017, when they reached the playoffs they had between 39 and 42 games where they allowed 6 or more runs. In the last three seasons, they had significantly more games (between 50 and 55).
The following table shows the playoff seasons plus the last two seasons (data from Baseball Reference).
The second statistic to track is runs allowed of 6 or more occurs in no more than 25% of games.
Tracking Offense.
A successful offense gets runners on base and scores a high percentage of those baserunners. In 2024, the Diamondbacks scored the most runs of any team because they did those two things very well per this AZ Snake Pit article and this AZ Snake Pit article. My view is that to reach the playoffs, the Diamondbacks need to continue having an offense that is nearly as good as 2024.
When the Diamondbacks reached the playoffs, and in the last two seasons, they had an average of 11 or more baserunners per game. They scored at least 33.2% of those baserunners.
The third and fourth statistics to track are averaging at least 11 baserunners per game and scoring at least a third of those baserunners.
Games when the Diamondbacks score 2 runs or less are usually very discouraging for fans. In seasons when the Diamondbacks reached the playoffs they never had more than 43 such games. In the last three seasons they improved that statistic, lowering it to 37 or less games.
The fifth statistic to track is runs scored of 2 runs of less in a game happens in less than 25% of their games.
The following table shows the playoff seasons plus the last two seasons (data from Baseball Reference). The accuracy of the data is higher in 2024 & 2025 due to in-season tracking (and because baserunners scored excluded errors, grounded into double plays, wild pitches, and passed balls).
Summary.
During the season, whether the Diamondbacks are playing well enough to reach the playoffs can be tracked with five statistics:
- Pitching:
- Quality starts in at least 50% of games played.
- Runs allowed of 6 or more occurs in no more than 25% of games.
- Offense:
- Averaging at least 11 baserunners per game.
- Scoring at least a third of baserunners.
- Runs scored of 2 or less occurs in less than 25% of games.
